# Physics Module Form 5 Chapter 2- Electricity GCKL 2011 CHARGE AND ELECTRIC CURRENT

Size: px
Start display at page:

Download "Physics Module Form 5 Chapter 2- Electricity GCKL 2011 CHARGE AND ELECTRIC CURRENT"

Transcription

1 2.1 CHARGE AND ELECTRIC CURRENT Van de Graaf 1. What is a Van de Graaff generator? Fill in each of the boxes the name of the part shown. A device that... and... at high voltage on its dome. dome 2. You will feel a brief shock when your finger is brought close to the dome of the generator. (B) EXPLANATION i. When the motor of the Van de Graaff generator is switched on, it drives the rubber belt. This cause the rubber belt to rub against the roller and hence becomes charged. The charge is then carried by the moving belt up to the metal where it is collected. A large amount of charge is built up on the dome. ii. The electric field around the metal dome of the generator can produced a strong force of between the opposite charges. will suddenly accelerate from the finger to the dome of the generator and causes a spark. 2-1

2 iii. When the wire touches the dome, the microammeter needle is deflected. This shows that a is flowing through the galvanometer. iv. The electric current is produced by the flow of from earth through the galvanometer to the metal dome to neutralize the positive charges on its surface. v. The metal dome can be safely touched with the finger as all the positive charges on it have been. 2. What will happen if the charged dome of the Van de Graaff is connected to the earth via a microammeter? Explain. There is a...of the pointer of the meter. This indicates an electric current... The microammeter needle is returned to its... position when the Van de Graaf is switched off. 3. Predict what will happen if a discharging metal sphere to the charged dome. When the discharging metal sphere is brought near the charged dome,... occurs. An electric current The flow of electrical charges produces

3 Electric Current 1. Electric current is defined as the In symbols, it is given as: I = Q t where I =... Q =... t =... (i) The SI unit of charge is (Ampere / Coulomb / Volt) (ii) The SI unit of time is (minute / second / hour) (iii) The SI unit of current is (Ampere / Coulomb / Volt) is equivalent to (Cs // C -1 s // Cs -1 ) I t (iv) By rearranging the above formula, Q = ( It / t / I ) 3. 1 Coulomb (C) = 1 Ampere Second (As) 4. Example : Charge of 1 electron =.. Charge of 1 proton =. 5. Total Charge : 2-3

4 Electric Field a. An electric field is a...in which an... experiences a... b. An electric field can be represented by a number of lines indicate both the... and...of the field. c. The principles involved in drawing electric field lines are : (i) electric field lines always extend from a... object to a...-charged object to infinity, or from... to a...-charged object, (ii) electric field lines never... each other, (iii) electric field lines are...in a... electric field. EFFECT OF AN ELECTRIC FIELD ON A PING PONG BALL Observation: (a) The ball will still remain... This is because the force exert on the ball by the... plate is... to the force exerted on it by the... plate. (a) (b) If the ping pong ball is displaced to the right to touch the... plate, it will then be charged with... charge and will be pushed... the... plate. (b) (c) (c) When the ping pong ball touches the... plate, it will be charged with... charge and will be pushed... the... plate. This process repeats again and again, causes the ping pong ball... to and fro continuously between the two plates. 2-4

5 Conclusion 1. Electric field is a Like charges... each other but opposite charges... each other. 3. Electric field lines are... in an electric field. The direction of the field lines is from... to... EXERCISE C of charge flows through a wire in 10 s. What is the current in the wire? 2. A charge of 300 C flow through a bulb in every 2 minutes. What is the electric current in the bulb? 3. The current in a lamp is 0.2 A. Calculate the amount of electric charge that passes through the lamp in 1 hour. 4. If a current of 0.8 A flows in a wire, how many electrons pass through the wire in one minute? (Given: The charge on an electron is 1.6 x C) 2-5

6 An electric current of 200 ma flows through a resistor for 3 seconds, what is the (a) (b) electric charge the number of electrons which flow through the resistor? 2.2 IDEAS OF POTENTIAL DIFFERENCE (a) (b) X Y P Q Pressure at point P is... than the pressure at point Q Water will flow from... to...when the valve is opened. This due to the... in the pressure of water Gravitational potential energy at X is... than the gravitational potential energy at Y. The apple will fall from... to...when the apple is released. This due to the... in the gravitational potential energy. 2-6

7 (c) Similarly, Point A is connected to...terminal Point B is connected to...terminal Electric potential at A is... than the electric potential at B. Electric current flows from A to B, passing the bulb in the circuit and...the bulb. This is due to the electric... between the two terminals. As the charges flow from A to B, work is done when electrical energy is transformed to... and...energy. The... between two points in a circuit is defined as the amount of work done, W when one coulomb of charge passes from one point to the other point in an electric field. The potential difference,v between the two points will be given by: V = Work W Quantityofcharge = Q A Bulb where W is work or energy in Joule (J) Q is charge in Coulomb (C) B 2-7

8 EXPERIMENT 1: TO INVESTIGATE THE RELATIONSHIP BETWEEN CURRENT AND POTENTIAL DIFFERENCE FOR AN OHMIC CONDUCTOR. (a) (b) Figure (a) and figure (b) show two electrical circuits. Why do the ammeters show different readings? Why do the bulbs light up with different intensity? Referring to the figure (a) and (b) complete the following table: (a) Inference (b) Hypothesis (c) Aim (d) Variables The current flowing through the bulb is influenced by the potential difference across it. To determine the relationship between current and potential difference for a constantan wire. (i) manipulated variable : (ii) responding variable : (iii) fixed variable : Apparatus / materials : 2-8

9 Method : Tabulation of data : 1. Set up the apparatus as shown in the figure. 2. Turn on the switch and adjust the rheostat so that the ammeter reads the current, I= 0.2 A. 3. Read and record the potential difference, V across the wire. Current,I/A Volt, V/V Analysis of data : Draw a graph of V against I. 2-9

10 Discussion : 1. From the graph plotted. (a) What is the shape of the V-I graph?...i is a straight line that passes through origin (b) What is the relationship between V and I? The resistance, R, of the constantan wire used in the experiment is equal to the gradient of the V-I graph. Determine the value of R. 3. What is the function of the rheostat in the circuit? Conclusion : rough it increases as long as... Ohm s Law (a) Ohm s law states that the electric current, I flowing through a conductor is directly proportional to the potential difference across the ends of the ohmic conductor, if temperature and other physical conditions remain constant (b) By Ohm s law: V I V I = constant 2-10

11 The temperature of the conductor The type of the material of the conductor The cross-sectional area of the conductor, A Length of the conductor, l Physics Module Form 5 Chapter 2- Electricity GCKL 2011 (c) The constant is known as... of the conductor. (d) The unit of resistance is Factors Affecting Resistance 1. The resistance of a conductor is a measure of the ability of the conductor to (resist / allow) the flow of an electric current through it. 2. From the formula V = IR, the current I is (directly / inversely) proportional to the resistance, R. 3. Write down the relevant hypothesis for the factors affecting the resistance in the table below. Factors Diagram Hypothesis Graph 4. From, the following can be stated: Hence, resistance of a conductor, R 2-11

12 So R or R = where = resistivity of the substance 5. i) Electric charge, Q = ( It / t I / t I ) ii) Work done, W = (QV / Q V / V Q ) EXERCISE If a charge of 5.0 C flows through a wire and the amount of electrical energy converted into heat is 2.5 J. Calculate the potential differences across the ends of the wire. 2. A light bulb is switched on for a period of time. In that period of time, 5 C of charges passed through it and 25 J of electrical energy is converted to light and heat energy. What is the potential difference across the bulb? 3. The potential difference of 10 V is used to operate an electric motor. How much work is done in moving 3 C of electric charge through the motor? 2-12

13 4. When the potential difference across a bulb is 20 V, the current flow is 3 A. How much work done to transform electrical energy to light and heat energy in 50 s? 3 A 20 V Bulb 5. What is the potential difference across a light bulb of resistance 5 when the current that passes through it is 0.5 A? 6. What is the value of the resistor in the figure, if the dry cells supply 2.0 V and the ammeter reading is 0.5 A? 7. If the bulb in the figure has a resistance of 6, what is the reading shown on the ammeter, if the dry cells supply 3 V? 8. If a current of 0.5 A flows through the resistor of 3 in the figure, calculate the voltage supplied by the dry cells? 2-13

14 9. Referring to the diagram on the right, calculate (a) The current flowing through the resistor. I 5 12 V (b) The amount of electric charge that passes through the resistor in 30 s (c) The amount of work done to transform the electric energy to the heat energy in 30 s. 10. The graph shows the relationship between the potential difference, V and current, I flowing through two conductors, X and Y. a) Calculate the resistance of conductor X. 8 V/V X Y 2 b) Calculate the resistance of conductor Y I/A c) If the cross sectional area of X is 5.0 x 10-6 m 2, and the length of X is 1.2 m, calculate its resistivity. 2-14

15 2.3 SERIES AND PARALLEL CIRCUITS Current Flow and Potential Difference in Series and Parallel Circuit SERIES CIRCUIT PARALLEL CIRCUIT 1. Effective Resistance: R = 2. Current: 3. Potential Difference: V = 1. Effective Resistance: R = 2. Current: 3. Potential Difference: V = Effective resistance, R (a) (b) 2-15

16 (c) (d) (e) (f) (g) (h) EXERCISE The two bulbs in the figure have a resistance of 2 and 3 respectively. If the voltage of the dry cell is 2.5 V, calculate (a) the effective resistance, R of the circuit (b) the main current, I in the circuit (c) the potential difference across each bulb. 2-16

17 2. There are two resistors in the circuit shown. Resistor R 1 has a resistance of 1. If a 3V voltage causes a current of 0.5A to flow through the circuit, calculate the resistance of R The electrical current flowing through each branch, I 1 and I 2, is 5 A. Both bulbs have the same resistance, which is 2. Calculate the voltage supplied. 4. The voltage supplied to the parallel is 3 V. R 1 and R 2 have a resistance of 5 and 20. Calculate (a) the potential difference across each resistor (b) the effective resistance, R of the circuit (c) the main current, I in the circuit (d) the current passing through each resistor 2-17

18 2.4 ELECTROMOTIVE FORCE AND INTERNAL RESISTANCE Electromotive force Figure (a) Figure (b) Voltmeter reading, e.m.f. Voltmeter reading, potential difference, V < e.m.f., E E, r R No current flow Current flowing 1. An electrical circuit is set up as shown in figure (a). A high resistance voltmeter is connected across a dry cell which labeled 1.5 V. a) Figure (a) is (an open circuit / a closed circuit) b) There is (current flowing / no current flowing) in the circuit. The bulb (does not light up / lights up) c) The voltmeter reading shows the (amount of current flow across the dry cell / potential difference across the dry cell) 2-18

19 2. The switch is then closed as shown in figure (b). a) Figure (b) is (an open circuit / a closed circuit) b) There is (current flowing / no current flowing) in the circuit. The bulb (does not light up / lights up) c) The voltmeter reading is the (potential difference across the dry cell / potential difference across the bulb / electromotive force). d) The reading of the voltmeter when the switch is closed is (lower than/ the same as / higher than) when the switch is open. e) State the relationship between e.m.f, E, potential difference across the bulb, V R and drop in potential difference due to internal resistance, V r. 3. a) Why is the potential difference across the resistor not the same as the e.m.f. of the battery? The potential drops as much as V across the internal resistance b) Determine the value of the internal resistance. Since E = V Ir = r r = Therefore, the value of the internal resistance is 2-19

20 EXERCISE A voltmeter connected directly across a battery gives a reading of 1.5 V. The voltmeter reading drops to 1.35 V when a bulb is connected to the battery and the ammeter reading is 0.3 A. Find the internal resistance of the battery. 2 A circuit contains a cell of e.m.f 3.0 V and internal resistance, r. If the external resistor has a value of 10.0 and the potential difference across it is 2.5 V, find the value of the current, I in the circuit and the internal resistance, r. 3 A simple circuit consisting of a 2 V dry cell with an internal resistance of 0.5. When the switch is closed, the ammeter reading is 0.4 A. Calculate (a) the voltmeter reading in open circuit (b) the resistance, R (c) the voltmeter reading in closed circuit 2-20

21 4 Find the voltmeter reading and the resistance, R of the resistor. e.m.f. 5 A cell of e.m.f., E and internal resistor, r is connected to a rheostat. The ammeter reading, I and the voltmeter reading, V are recorded for different resistance, R of the rheostat. The graph of V against I is as shown. / V From the graph, determine a) the electromotive force, e.m.f., E /A b) b) the internal resistor, r of the cell 2-21

22 2.5 ELECTRICAL ENERGY AND POWER Electrical Energy Electrical Energy and Electrical Power 1. Potential difference, V across two points is the energy,e dissipated or transferred by a coulomb of charge, Q that moves across the two points. 2. Therefore, 3. Hence, 4. Power is defined as the rate of energy dissipated or transferred. 5. Hence, E = VQ Power, P = Potential difference, V = Energy dissipated, E time, t Electrical energy dissipated, E Charge, Q From the definition of potential difference, V Electrical Energy, E Electrical Power, P Power is the rate of transfer of electrical energy, Electrical energy converted, E ; where Q = It Hence, ; where V = IR Hence, ; where I = V R SI unit : SI unit : 2-22

23 Power Rating and Energy Consumption of Various Electrical Appliances 1. The amount of electrical energy consumed in a given period of time can be calculated by Energy consumed = Power rating x Time E = Pt where energy, E is in Joules power, P is in watts time, t is in seconds COST OF ENERGY Appliance Quantity Power / W Power / kw Time Energy Consumed (kwh) Bulb hours Refrigerator hours Kettle hours Iron hours Total energy consumed, E = = kwh Cost = kwh x RM 0.28 = RM 2-23

24 EXERCISE How much power dissipated in the bulb? (a) R = 10 5 V (b) R = 10 R = 10 5 V 2. V= 15V I R 1=2 R 2=4 R 3=4 Calculate : (a) the current, I in the circuit (b) the energy released in R 1 in 10 s. (b) the electrical energy supplied by the battery in 10 s. 2-24

25 3. An electric motor is used to lift a load of mass 2 kg to a height 5 m in 2.5 s. If the supply voltage is 12 V and the flow of current in the motor is 5.0 A, calculate (a) Energy input to the motor (b) Useful energy output of the motor (c) Efficiency of the motor 2-25

26 REINFORCEMENT EXERCISE CHAPTER 2 Part A: Objective Questions Which of the following diagrams shows the correct electric field? 4. A current of 5 A flows through an electric heater when it is connected to the 240 V main supply. How much heat is released after 2 minutes? A J B C D J J J 5. An electric bulb is labeled 240V, 60W. How much energy is used by the bulb in one minute if the bulb is connected to a 240V power supply? 2. A B C D 60 J 360 J 600 J 3600 J Diagram 1 Diagram1show a lamp connected to a resistor and abattery. Calculate the power used by the light bulb. 6. The diagram shows a cell of negligible internal resistance connected to two resistors A B C D 6 W 12 W 20 W 50 W 3. When the switch is on, the current that flows in an electronic advertisement board is 3.0 x 10-5 A. What is the number of electrons flowing in the advertisement board when it is switched on for 2 hours? [ Charge of an electron = 1.6 x C ] A 3.84 x B 1.67 x C 1.35 x What is the value of current, I? A 0.45 A B 0.40 A C 0.25 A 2-26

### Physics Module Form 5 Chapter 2- Electricity GCKL 2011 CHARGE AND ELECTRIC CURRENT

2.1 CHARGE AND ELECTRIC CURRENT Van de Graaf 1. What is a Van de Graaff generator? Fill in each of the boxes the name of the part shown. A device that produces and store electric charges at high voltage

### 7.1 ANALYSING ELECTRIC FIELDS AND CHARGE FLOW

7.1 ANALYSING ELECTRIC FIELDS AND CHARGE FLOW State the relationship between electron and electric current Where does charge come from? Matter is made up of tiny particles called atoms. At the center of

### Insulators Non-metals are very good insulators; their electrons are very tightly bonded and cannot move.

SESSION 11: ELECTRIC CIRCUITS Key Concepts Resistance and Ohm s laws Ohmic and non-ohmic conductors Series and parallel connection Energy in an electric circuit X-planation 1. CONDUCTORS AND INSULATORS

### Test Review Electricity

Name: Date: 1. An operating television set draws 0.71 ampere of current when connected to a 120-volt outlet. Calculate the time it takes the television to consume 3.0 10 5 joules of electric energy. [Show

### ELECTRICITY. Prepared by: M. S. KumarSwamy, TGT(Maths) Page

ELECTRICITY 1. Name a device that helps to maintain a potential difference across a conductor. Cell or battery 2. Define 1 volt. Express it in terms of SI unit of work and charge calculate the amount of

### CLASS X- ELECTRICITY

Conductor- Insulator: Materia Materials through which electric current cannot pass are called insulators. Electric Circuit: A continuous a CLASS X- ELECTRICITY als through which electric current can pass

### Electron Theory of Charge. Electricity. 1. Matter is made of atoms. Refers to the generation of or the possession of electric charge.

Electricity Refers to the generation of or the possession of electric charge. There are two kinds of electricity: 1. Static Electricity the electric charges are "still" or static 2. Current Electricity

### CHAPTER 1 ELECTRICITY

CHAPTER 1 ELECTRICITY Electric Current: The amount of charge flowing through a particular area in unit time. In other words, it is the rate of flow of electric charges. Electric Circuit: Electric circuit

### Electricity. dronstudy.com

Electricity Electricity is a basic part of our nature and it is one of our most widely used forms of energy. We use electricity virtually every minute of every day for example in lighting, heating, refrigeration,

### Section 1 Electric Charge and Force

CHAPTER OUTLINE Section 1 Electric Charge and Force Key Idea questions > What are the different kinds of electric charge? > How do materials become charged when rubbed together? > What force is responsible

### Electric Charge. Electric Charge ( q ) unbalanced charges positive and negative charges. n Units Coulombs (C)

Electric Charge Electric Charge ( q ) unbalanced charges positive and negative charges n Units Coulombs (C) Electric Charge How do objects become charged? Types of materials Conductors materials in which

### Physics 7B-1 (A/B) Professor Cebra. Winter 2010 Lecture 2. Simple Circuits. Slide 1 of 20

Physics 7B-1 (A/B) Professor Cebra Winter 2010 Lecture 2 Simple Circuits Slide 1 of 20 Conservation of Energy Density In the First lecture, we started with energy conservation. We divided by volume (making

### Electromagnetism Checklist

Electromagnetism Checklist Elementary Charge and Conservation of Charge 4.1.1A Convert from elementary charge to charge in coulombs What is the charge in coulombs on an object with an elementary charge

### A Review of Circuitry

1 A Review of Circuitry There is an attractive force between a positive and a negative charge. In order to separate these charges, a force at least equal to the attractive force must be applied to one

### Name: Class: Date: 1. Friction can result in the transfer of protons from one object to another as the objects rub against each other.

Class: Date: Physics Test Review Modified True/False Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true. 1. Friction can result in

### ELECTRICITY. Electric Circuit. What do you already know about it? Do Smarty Demo 5/30/2010. Electric Current. Voltage? Resistance? Current?

ELECTRICITY What do you already know about it? Voltage? Resistance? Current? Do Smarty Demo 1 Electric Circuit A path over which electrons travel, out through the negative terminal, through the conductor,

### Chapter 3: Electric Current And Direct-Current Circuits

Chapter 3: Electric Current And Direct-Current Circuits 3.1 Electric Conduction 3.1.1 Describe the microscopic model of current Mechanism of Electric Conduction in Metals Before applying electric field

### 6. In a dry cell electrical energy is obtained due to the conversion of:

1. If a wire of uniform area of cross section is cut into two halves (equal in size), the resistivity of each part will be: a) Halved. b) Doubled. c) Becomes four times its initial value. d) Remains the

### 1.3 Most domestic appliances are connected to the mains electricity with a plug. Explain why a plug needs a live and a neutral wire.

4-2 Electricity Physics.0 Most domestic appliances are connected to the mains electricity.. What is the frequency of mains electricity? Tick one box [ mark].05 A 50 Hz 230 V.2 What is the potential difference

### Review. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

Review Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. When more devices are added to a series circuit, the total circuit resistance: a.

### Electricity Courseware Instructions

Physics Electricity Courseware Instructions This courseware acts as a supplement to the classroom instruction. The five sections on the following slide link to the topic areas. Following the topic area

### ELECTRICITY UNIT REVIEW

ELECTRICITY UNIT REVIEW S1-3-04: How does the Atomic Model help to explain static electricity? 1. Which best describes static electricity? a) charges that can be collected and held in one place b) charges

### 9. Which of the following is the correct relationship among power, current, and voltage?. a. P = I/V c. P = I x V b. V = P x I d.

Name: Electricity and Magnetism Test Multiple Choice Identify the choice that best completes the statement. 1. Resistance is measured in a unit called the. a. ohm c. ampere b. coulomb d. volt 2. The statement

### Electricity Review completed.notebook. June 13, 2013

Which particle in an atom has no electric charge associated with it? a. proton c. neutron b. electron d. nucleus Jun 12 9:28 PM The electrons in a metal sphere can be made to move by touching it with a

### Revision checklist SP10. SP10 Electricity and Circuits. SP10a Electric circuits. SP10b Current and potential difference

Electricity and Circuits a Electric circuits Describe the basic structure of an atom (positions, relative masses and relative charges of protons, neutrons and electrons). Recognise the circuit symbols

### Material World Electricity and Magnetism

Material World Electricity and Magnetism Electrical Charge An atom is composed of small particles of matter: protons, neutrons and electrons. The table below describes the charge and distribution of these

### What is an Electric Current?

Electric Circuits NTODUCTON: Electrical circuits are part of everyday human life. e.g. Electric toasters, electric kettle, electric stoves All electrical devices need electric current to operate. n this

### Resistivity and Temperature Coefficients (at 20 C)

Homework # 4 Resistivity and Temperature Coefficients (at 0 C) Substance Resistivity, Temperature ( m) Coefficient, (C ) - Conductors Silver.59 x 0-0.006 Copper.6 x 0-0.006 Aluminum.65 x 0-0.0049 Tungsten

### Closed loop of moving charges (electrons move - flow of negative charges; positive ions move - flow of positive charges. Nucleus not moving)

Unit 2: Electricity and Magnetism Lesson 3: Simple Circuits Electric circuits transfer energy. Electrical energy is converted into light, heat, sound, mechanical work, etc. The byproduct of any circuit

### Electricity. Prepared by Juan Blázquez, Alissa Gildemann. Electric charge is a property of all objects. It is responsible for electrical phenomena.

Unit 11 Electricity 1. Electric charge Electric charge is a property of all objects. It is responsible for electrical phenomena. Electrical phenomena are caused by the forces of attraction and repulsion.

### (b) State the relation between work, charge and potential difference for an electric circuit.

Question Bank on Ch-Electricity 1. (a) Define the S.I unit of potential difference. (b) State the relation between work, charge and potential difference for an electric circuit. Calculate the potential

### PHYSICS FORM 5 ELECTRICAL QUANTITES

QUANTITY SYMBOL UNIT SYMBOL Current I Amperes A Voltage (P.D.) V Volts V Resistance R Ohm Ω Charge (electric) Q Coulomb C Power P Watt W Energy E Joule J Time T seconds s Quantity of a Charge, Q Q = It

### Electric current is a flow of electrons in a conductor. The SI unit of electric current is ampere.

C h a p t e r at G l a n c e 4. Electric Current : Electric current is a flow of electrons in a conductor. The SI unit of electric current is ampere. Current = Charge time i.e, I = Q t The SI unit of charge

### 52 VOLTAGE, CURRENT, RESISTANCE, AND POWER

52 VOLTAGE, CURRENT, RESISTANCE, AND POWER 1. What is voltage, and what are its units? 2. What are some other possible terms for voltage? 3. Batteries create a potential difference. The potential/voltage

### Section 1: Electric Charge and Force

Electricity Section 1 Section 1: Electric Charge and Force Preview Key Ideas Bellringer Electric Charge Transfer of Electric Charge Induced Charges Charging by Contact Electric Force Electric Field Lines

### Which of the following is the SI unit of gravitational field strength?

T5-2 [122 marks] 1. A cell is connected in series with a 2.0Ω resistor and a switch. The voltmeter is connected across the cell and reads 12V when the switch is open and 8.0V when the switch is closed.

Forces Read Chapter 7; pages: 191-221 Objectives: - Describe how electrical charges exert forces on each other; Compare the strengths of electric and gravitational forces; Distinguish between conductors

### What does it mean for an object to be charged? What are charges? What is an atom?

What does it mean for an object to be charged? What are charges? What is an atom? What are the components of an atom? Define the following: Electric Conductor Electric Insulator Define the following: Electric

### Question 3: How is the electric potential difference between the two points defined? State its S.I. unit.

EXERCISE (8 A) Question : Define the term current and state its S.I unit. Solution : Current is defined as the rate of flow of charge. I = Q/t Its S.I. unit is Ampere. Question 2: Define the term electric

### 1. The diagram shows the electric field lines produced by an electrostatic focussing device.

1. The diagram shows the electric field lines produced by an electrostatic focussing device. Which one of the following diagrams best shows the corresponding equipotential lines? The electric field lines

### Physics 1214 Chapter 19: Current, Resistance, and Direct-Current Circuits

Physics 1214 Chapter 19: Current, Resistance, and Direct-Current Circuits 1 Current current: (also called electric current) is an motion of charge from one region of a conductor to another. Current When

### S1 Bright Sparks Summary Notes

S1 Bright Sparks Summary Notes Electronics Electronic systems 1 We are learning about the different parts of electronic systems. In our modern world we use electronic systems many times a day. In fact,

### Waves Final Review. Name: Date: 1. On which one of the following graphs is the wavelength λ and the amplitude a of a wave correctly represented?

Name: Date: Waves Final Review 1. On which one of the following graphs is the wavelength λ and the amplitude a of a wave correctly represented? A. Displacement λ a Distance along wave B. Displacement λ

### 8. Electric circuit: The closed path along which electric current flows is called an electric circuit.

GIST OF THE LESSON 1. Positive and negative charges: The charge acquired by a glass rod when rubbed with silk is called positive charge and the charge acquired by an ebonite rod when rubbed with wool is

### Electricity CHAPTER ELECTRIC CURRENT AND CIRCUIT

CHAPTER 12 Electricity Electricity has an important place in modern society. It is a controllable and convenient form of energy for a variety of uses in homes, schools, hospitals, industries and so on.

### RECALL?? Electricity concepts in Grade 9. Sources of electrical energy Current Voltage Resistance Power Circuits : Series and Parallel

Unit 3C Circuits RECALL?? Electricity concepts in Grade 9. Sources of electrical energy Current Voltage Resistance Power Circuits : Series and Parallel 2 Types of Electricity Electrostatics Electricity

### 1 of 23. Boardworks Ltd Electrical Power

1 of 23 Boardworks Ltd 2016 Electrical Power Electrical Power 2 of 23 Boardworks Ltd 2016 What is electrical power? 3 of 23 Boardworks Ltd 2016 Electrical power is the rate at which energy is transferred

### 10 N acts on a charge in an electric field of strength 250 N.C What is the value of the charge?

Year 11 Physics Electrical Energy in the Home Name: 1. Draw the electric field lines around a) a single positive charge b) between two opposite charged bodies c) two parallel plates + + + + + + + - - -

### PhysicsAndMathsTutor.com

Electricity May 02 1. The graphs show the variation with potential difference V of the current I for three circuit elements. PhysicsAndMathsTutor.com When the four lamps are connected as shown in diagram

CHAPTER 12 ELECTRICITY Electricity is a general term that encompasses a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena such

### EXPERIMENT 12 OHM S LAW

EXPERIMENT 12 OHM S LAW INTRODUCTION: We will study electricity as a flow of electric charge, sometimes making analogies to the flow of water through a pipe. In order for electric charge to flow a complete

### 1 Written and composed by: Prof. Muhammad Ali Malik (M. Phil. Physics), Govt. Degree College, Naushera

CURRENT ELECTRICITY Q # 1. What do you know about electric current? Ans. Electric Current The amount of electric charge that flows through a cross section of a conductor per unit time is known as electric

### Science Practice Exam. Chapters 5 and 14

Science Practice Exam Chapters 5 and 14 FORMULAS Science and Technology FORMULAS C: concentration m: quantity of solute v: quantity of solution V: potential difference R: resistance I: electric current

### Electricity. Part 1: Static Electricity

Electricity Part 1: Static Electricity Introduction: Atoms Atoms are made up of charged particles. Atoms are made of 3 subatomic particles: Electrons protons, electrons and neutrons. Protons () Charge

GRADE 11F: Physics 4 Current electricity UNIT 11FP.4 10 hours About this unit This unit is the fourth of five units on physics for Grade 11 foundation. The unit is designed to guide your planning and teaching

### ELECTRIC CIRCUITS. Checklist. Exam Questions

ELECTRIC CIRCUITS Checklist Make sure you can. State Ohm's law in words. Determine relationship between current, potential difference and resistance at constant temperature using a simple circuit Draw,

### SNC1DI Unit Review: Static & Current Electricity

SNC1DI Unit Review: Static & Current Electricity 1. Be able to recognize the definitions for the following terms: Friction Contact Induction Lightning Electrostatic Series Pithball electroscope Insulators

### TSOKOS LSN 5-1 TO 5-5 TEST REVIEW

IB HYSICS Name: DEIL HYSICS eriod: Date: # Marks: BADDEST CLASS ON CAMUS TSOKOS LSN 5-1 TO 5-5 TEST REIEW 4. This question is about forces on charged particles. (a) (b) A charged particle is situated in

### Electricity. Chapter 21

Electricity Chapter 21 Electricity Charge of proton Positive Charge of electron Negative Charge of neutron NONE Atoms have no charge because the charges of the protons and electrons cancel each other out.

### 5. ELECTRIC CURRENTS

5. ELECTRIC CURRENTS TOPIC OUTLINE Section Recommended Time Giancoli Section 5.1 Potential Difference, Current, Resistance 5.2 Electric Circuits 3h 19.1, 19.2 6.2 Electric Field and Force 6.3 Magnetic

### Electroscope Used to are transferred to the and Foil becomes and

Electricity Notes Chapter 17 Section 1: Electric Charge and Forces Electric charge is a variety of independent all with one single name. Electricity is related to, and both (-) and (+) carry a charge.

### Preliminary Course Physics Module 8.3 Electrical Energy in the Home Summative Test. Student Name:

Summative Test Student Name: Date: / / IMPORTANT FORMULAE I = Q/t V = I.R R S = R 1 + R 2 +.. 1/R P = 1/R 1 + 1/R 2 + P = V.I = I 2.R = V 2 /R Energy = V.I.t E = F/q Part A. Multiple Choice Questions 1-20.

### UNIT II CURRENT ELECTRICITY

UNIT II CUENT ELECTICITY Weightage : 07 Marks Electric current; flow of electric charges in a metllic conductor, drift velocity, mobility and their relation with electric current. Ohm s law electrical

### Dynamic Electricity. All you need to be an inventor is a good imagination and a pile of junk. -Thomas Edison

Dynamic Electricity All you need to be an inventor is a good imagination and a pile of junk. -Thomas Edison Review Everything is made of atoms which contain POSITIVE particles called PROTONS and NEGATIVE

### Electric Currents and Circuits

Electric Currents and Circuits Producing Electric Current Electric Current flow of charged particles Need a potential difference to occur Conventional Current- flow of positive charges flowing from positive

### Readings Distance (m) Time (s) Velocity (m s -1 ) Force (N) 1 0,15 1 0,15 1,02 2 0,30 1,5 0,2 0,51 3 0,45 1,75 0,257 0,26 4 1,00 No effect 0 0

Contextual questions 1 Two identical, light, graphite-coated balls, X and Y, both have a charge of -3 10-12 C The balls are fixed to a horizontal, insulated X Y 5 cm surface The distance between the centres

### LESSON 5: ELECTRICITY II

LESSON 5: ELECTRICITY II The first two points are a review of the previous lesson 1.1.ELECTRIC CHARGE - Electric charge is a property of all objects and is responsible for electrical phenomena. -All matter

### What is electricity? Charges that could be either positive or negative and that they could be transferred from one object to another.

Electricity What is electricity? Charges that could be either positive or negative and that they could be transferred from one object to another. What is electrical charge Protons carry positive charges

### This week. 3/23/2017 Physics 214 Summer

This week Electrical Circuits Series or parallel that s the question. Current, Power and Energy Why does my laptop battery die? Transmission of power to your home Why do we have big transmission towers?

### This week. 6/2/2015 Physics 214 Summer

This week Electrical Circuits Series or parallel that s the question. Current, Power and Energy Why does my laptop battery die? Transmission of power to your home Why do we have big transmission towers?

### Electricity Final Unit Final Assessment

Electricity Final Unit Final Assessment Name k = 1/ (4pe 0 ) = 9.0 10 9 N m 2 C -2 mass of an electron = 9.11 10-31 kg mass of a proton = 1.67 10-27 kg G = 6.67 10-11 N m 2 kg -2 C = 3 x10 8 m/s Show all

### 15 - THERMAL AND CHEMICAL EFFECTS OF CURRENTS Page 1 ( Answers at the end of all questions )

5 - THERMAL AND CHEMICAL EFFECTS OF CURRENTS Page A heater coil is cut into two equal parts and only one part is now used in the heater. The heat generated will now be four times doubled halved ( d one-fourth

### STUDY GUIDE CHAPTER 5 ELECTRICITY AND MAGNETISM 1) ASSOCIATE ELEMENTARY PARTICLES WITH THEIR ELECTRICAL CHARGE

Name Date STUDY GUIDE CHAPTER 5 ELECTRICITY AND MAGNETISM 1) ASSOCIATE ELEMENTARY PARTICLES WITH THEIR ELECTRICAL CHARGE Scientists now know that an atom is composed of even smaller particles of matter:

### 1 Fig. 3.1 shows the variation of the magnetic flux linkage with time t for a small generator. magnetic. flux linkage / Wb-turns 1.

1 Fig. 3.1 shows the variation of the magnetic flux linkage with time t for a small generator. 2 magnetic 1 flux linkage / 0 10 2 Wb-turns 1 2 5 10 15 t / 10 3 s Fig. 3.1 The generator has a flat coil

### Chapter 33 - Electric Fields and Potential. Chapter 34 - Electric Current

Chapter 33 - Electric Fields and Potential Chapter 34 - Electric Current Electric Force acts through a field An electric field surrounds every electric charge. It exerts a force that causes electric charges

### Circuits-Ohm's Law. 1. Which graph best represents the relationship between the electrical power and the current in a resistor that obeys Ohm s Law?

1. Which graph best represents the relationship between the electrical power and the current in a resistor that obeys Ohm s Law? 2. A potential drop of 50 volts is measured across a 250- ohm resistor.

### Curriculum Interpretation Electricity and Magnetism. Lee Wai Kit

Curriculum Interpretation Electricity and Magnetism Lee Wai Kit Electricity and Magnetism 4.1 Electrostatics 4.2 Circuits and domestic electricity 4.3 Electromagnetism 4.1 Electrostatics electric charges

### ELECTRICAL Quantities

1 ELECTRICAL Quantities Friction And Charge When two materials rub together the contact between their surfaces may cause: a) the surfaces to become hot and show wear and tear. b) the surfaces to become

### Part 4: Electricity & Magnetism

Part 4: Electricity & Magnetism Notes: Magnetism Magnetism Magnets: 1.Have a north and south pole 2.Like poles repel; opposite poles attract - The larger the distance between the magnets, the weaker the

### 10/14/2018. Current. Current. QuickCheck 30.3

Current If QCurrent is the total amount of charge that has moved past a point in a wire, we define the current I in the wire to be the rate of charge flow: The SI unit for current is the coulomb per second,

### SECONDARY SCHOOL ANNUAL EXAMINATIONS 2002 Educational Assessment Unit - Education Division

SECONDARY SCHOOL ANNUAL EXAMINATIONS 2002 Educational Assessment Unit - Education Division FORM 4 PHYSICS TIME: 1 hr 30 min NAME: CLASS: Answer all the questions in the spaces provided on the Examination

### Unit 3 BLM Answers UNIT 3 BLM 3-46

UNIT 3 BLM 3-46 Unit 3 BLM Answers BLM 3-3, Charge Transfer Diagrams 1. Positively charged objects should have more (+) than ( ). Negatively charged objects should have more ( ) than (+). 2. They must

### Electricity Test Review

Electricity Test Review Definitions; Series Circuit, Parallel Circuit, Equivalent Resistance, Fuse, Circuit Breaker, kilowatt hour, load, short circuit, dry cell, wet cell, fuel cells, solar cells, fossil

### Chapter 7. Electricity. Teacher Answer Key. Broughton High School of Wake County

Teacher Answer Key Broughton High School of Wake County 1 Chapter 7 Electricity Physical Science Vocabulary 2 Vocabulary for Chapter 7 Electricity Vocabulary Word Definition 1. Charging by Contact 2. Charging

### Lesson Plan: Electric Circuits (~130 minutes) Concepts

Lesson Plan: Electric Circuits (~130 minutes) Concepts 1. Electricity is the flow of electric charge (electrons). 2. Electric Charge is a property of subatomic particles. 3. Current is the movement of

### Module 1 Units 3,4,5

Module 1 Units 3,4,5 1. What is matter? Anything that occupies space or has mass 2. What are the two general categories of substances? Elements and compounds 3. How many naturally occurring elements are

### Electricity Worksheet (p.1) All questions should be answered on your own paper.

Electricity Worksheet (p.1) 1. In terms of attraction and repulsion, how do negative particles affect negative particles? How do negatives affect positives? 2. What happens to electrons in any charging

### CAPACITORS / ENERGY STORED BY CAPACITORS / CHARGING AND DISCHARGING

PHYSICS A2 UNIT 4 SECTION 3: CAPACITANCE CAPACITORS / ENERGY STORED BY CAPACITORS / CHARGING AND DISCHARGING # Question CAPACITORS 1 What is current? Current is the rate of flow of charge in a circuit

### Direct Current (DC) Circuits

Direct Current (DC) Circuits NOTE: There are short answer analysis questions in the Participation section the informal lab report. emember to include these answers in your lab notebook as they will be

### MOTORS AND GENERATORS

DO PHYSCS ONLNE MOTORS AND GENERATORS view 1 Charge q Q [coulomb C] view 2 Current i [ampere A] view 3 Potential difference v V [volt V] Electric ield E [V.m -1 N.C -1 ] view 4 Resistance R [ohm ] view

### Look over Chapter 26 sections 1-7 Examples 3, 7. Look over Chapter 18 sections 1-5, 8 over examples 1, 2, 5, 8, 9,

Look over Chapter 26 sections 1-7 Examples 3, 7 Look over Chapter 18 sections 1-5, 8 over examples 1, 2, 5, 8, 9, 1)How to find a current in a wire. 2)What the Current Density and Draft Speed are. 3)What

### 5 Electrical currents

5 Electrical currents 5.1 Electric potential difference, current and resistance Assessment statements 5.1.1 Define electric potential difference. 5.1.2 Determine the change in potential energy when a charge

### SPH3U1 Lesson 01 Electricity

ELECTRIC CURRENT AND POTENTIAL DIFFERENCE LEARNING GOALS Students will: Define what is meant by electric current. Solve problems involving current, charge and time. Know the difference between electron

### Relating Voltage, Current and Resistance

Relating Voltage, Current and Resistance Using Ohm s Law in a simple circuit. A Simple Circuit Consists of:! A voltage source often a battery! A load such as a bulb! Conductors arranged to complete a circuit

### Electric Current & DC Circuits How to Use this File Electric Current & DC Circuits Click on the topic to go to that section Circuits

Slide 1 / 127 Slide 2 / 127 Electric Current & DC Circuits www.njctl.org Slide 3 / 127 How to Use this File Slide 4 / 127 Electric Current & DC Circuits Each topic is composed of brief direct instruction

### Chapter 3: Electric Current and Direct-Current Circuit

Chapter 3: Electric Current and Direct-Current Circuit n this chapter, we are going to discuss both the microscopic aspect and macroscopic aspect of electric current. Direct-current is current that flows

### 1) Two lightbulbs, one rated 30 W at 120 V and another rated 40 W at 120 V, are arranged in two different circuits.

1) Two lightbulbs, one rated 30 W at 120 V and another rated 40 W at 120 V, are arranged in two different circuits. a. The two bulbs are first connected in parallel to a 120 V source. i. Determine the

### Chapter 17 Electric Current and Resistance Pearson Education, Inc.c

Chapter 17 Electric Current and Resistance 2010 Pearson Education, Inc.c 1 Units of Chapter 17 Batteries and Direct Current Current and Drift Velocity Resistance and Ohm s Law Electric Power 2010 Pearson

### 4.2.1 Current, potential difference and resistance

4.2 Electricity Electric charge is a fundamental property of matter everywhere. Understanding the difference in the microstructure of conductors, semiconductors and insulators makes it possible to design

CURRENT ELECTRICITY CHAPTER 13 CURRENT ELECTRICITY Qs. Define Charge and Current. CHARGE Definition Flow of electron is known as Charge. It is denoted by Q. Unit Its unit is Coulomb. 1 Coulomb = 10(-6)