Name: Block: Date: NNHS Introductory Physics: MCAS Review Packet #4 Introductory Physics, High School Learning Standards for a Full First-Year Course

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1 Introductory Physics, High School Learning Standards for a Full First-Year Course I. C ONTENT S TANDARDS electricity and magnetism. 5.1 Recognize that an electric charge tends to be static on insulators and can move on and in conductors. Explain that energy can produce a separation of charges. 5.2 Develop qualitative and quantitative understandings of current, voltage, resistance, and the connections among them (Ohm s law). 5.3 Analyze simple arrangements of electrical components in both series and parallel circuits. Recognize symbols and understand the functions of common circuit elements (battery, connecting wire, switch, fuse, resistance) in a schematic diagram. 5.4 Describe conceptually the attractive or repulsive forces between objects relative to their charges and the distance between them (Coulomb s law). 5.5 Explain how electric current is a flow of charge caused by a potential difference (voltage), and how power is equal to current multiplied by voltage. 5.6 Recognize that moving electric charges produce magnetic forces and moving magnets produce electric forces. Recognize that the interplay of electric and magnetic forces is the basis for electric motors, generators, and other technologies.

2 1.) The diagram below shows two aluminum spheres. 2.) Why does a plastic rod have a negative charge after being rubbed with a piece of fur? A. The fur gives up protons to the rod. B. The rod gives up electrons to the air. C. The fur gains protons from the rod. D. The rod gains electrons from the fur. Aluminum sphere A contains a small negative charge and is touched by aluminum sphere B, which has a larger negative charge. Which of the following occurs next? A. Protons flow from sphere B to sphere A. B. Protons flow from sphere A to sphere B. C. Electrons flow from sphere B to sphere A. D. Electrons flow from sphere A to sphere B.

3 electricity and magnetism. 3.) A negatively charged rubber rod was brought near some small pieces of paper. The rod s charges repelled the negative charges in the pieces. Which of the following caused the repulsion of the negative charges? A. conduction B. gravitation C. induction D. insulation 4.) The figure below shows a neutral glass rod and a positively charged metal sphere. Which of the following best describes the movement of charges as this glass rod touches the sphere? A. Negative charges move from the sphere to the glass rod. B. Negative charges move from the glass rod to the sphere. C. Positive charges move from the sphere to the glass rod. D. Positive charges move from the glass rod to the sphere.

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6 5.) Which of the following describes an object that must have a net negative charge? A. It contains more molecules than atoms. B. It contains more electrons than protons. C. It is carrying an electric current. D. It is made of metal. 6.) An electric circuit is shown below. The accompanying table shows the current measured at different levels of resistance. Based on the data shown in the table, what is the voltage drop across the variable resistor? A. 1.5 V B. 6 V C. 9 V D. 12 V

7 7.) Mr. Jenkins constructed a circuit consisting of a variable source, wires, and a resistor. In order to triple the amount of current, how should he change the voltage of the source? A. make the voltage three times larger B. make the voltage one-third as great C. make the voltage nine times larger D. make the voltage one-ninth as great 8.) What is the voltage in a circuit with a current of 3 Amps and a total resistance of 12? A V B. 4 V C. 15 V D. 36 V

8 9.) The circuit diagram below shows three resistors, an ammeter, and a battery. 10.) Students in a physics lab are studying the circuit shown in the diagram below. How much current flows through the ammeter? A. 1.0 A B. 6.0 A C A D Which of the following options will double the current through the ammeter? A. replacing the battery with a 5 V battery B. adding a 30 resistor in parallel with R C. replacing the resistor with a 30 resistor D. adding a second 60 resistor in series with R

9 11.) A 72 W navigation unit on a commercial aircraft has a 24 V power supply and uses 3 A of electric current. What is the electrical resistance of the navigation unit? A. 4 B. 8 C. 13 D ) When a light bulb is turned on, energy changes from one form to another. Which of the following best describes this change? A. sound energy to light energy B. nuclear energy to light energy C. electrical energy to light energy D. magnetic energy to light energy

10 13.) Marta has a radio in her room. It requires electricity in order to play. Which of the following is necessary in order for electricity to move from the source to the radio? A. a circuit B. a magnet C. a light bulb D. an insulator decreasing in volume. 14.) An ammeter measures the current in the circuit shown below. When the piece of wire labeled X is replaced by a second identical R, which of the following happens to the current? A. It increases. B. It decreases. C. It goes to zero. D. It remains unchanged.

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12 15.) A student combs her hair with a hard rubber comb and then hangs the comb on a loop of light thread that is suspended from a hook as shown below. She immediately combs her hair with a second identical comb and hangs it on the second suspended loop of light thread. If the combing has caused a charge to accumulate on the combs, which of the following shows what will occur?

13 16.) The figures below show a light bulb connected to a battery in two different ways. When the switch in Figure 1 is closed the bulb will light. A plastic ring is inserted in the circuit as shown in Figure 2. What will happen when the switch is closed in Figure 2? A. The bulb will light just as it did in Figure 1. B. The bulb will be brighter than it was in Figure 1. C. The bulb will light, but will be less bright than it was in Figure 1. D. The bulb will not light at all.

14 17.) A student is testing materials to see if they conduct electricity. The student places each item shown at position X, making sure the object is in contact with the loose end of each wire. Which item will electricity flow through, causing the bulb to light?

15 18.) In the diagram below, the circuit has one battery and two identical light bulbs. 19.) A teenager removes the plastic wrapping from a CD. The pieces of wrap cling to her hand. Which of the following forces causes the wrap to cling to her hand? A. electrostatic B. gravitational C. magnetic D. net If one light bulb is removed, which of the following could replace it so that the remaining light bulb is dimmer? A. B. C. D.

16 20.) The distance between two charges is represented by d. In which of the following diagrams is the attractive force between the two charges the greatest? A. B. C. D. 21.) A magnetic compass is placed near an insulated copper wire. When the wire is connected to a battery, the compass needle changes position. Which of the following is the best explanation for the movement of the needle? A. The copper wire magnetizes the needle to create a force. B. The needle magnetizes the copper wire to create a force. C. The current in the wire produces a magnetic field and exerts a force on the needle. D. The insulation on the wire becomes energized and exerts a force on the needle.

17 Practice: Open-response question #1 BE SURE TO ANSWER AND LABEL ALL PARTS OF THE QUESTION. Show all your work (diagrams, tables, or computations) If you do the work in your head, explain in writing how you did the work. Look at the objects shown below. Some of these objects are conductors of electricity and some are insulators. a. List all the objects that are conductors. b. List all the objects that are insulators. c. Describe the difference between a conductor of electricity and an insulator of electricity.

18 Practice: Open-response question #2 BE SURE TO ANSWER AND LABEL ALL PARTS OF THE QUESTION. Show all your work (diagrams, tables, or computations) If you do the work in your head, explain in writing how you did the work. A circuit with three identical light bulbs is shown in the diagram below. QuickTime and a decompressor are needed to see this picture. a. Identify the symbol labeled J in the circuit. b. Describe what each light bulb does in each of the following situations: when switches 1 and 2 are open when switches 1 and 2 are closed when switch 1 is open and switch 2 is closed when switch 1 is closed and switch 2 is open