Physics 40S Final Exam Review Topics 2017

Transcription

1 Physics 40S Final Exam Review Topics 2017 Unit 1: Mechanics S4P Derive the special equations for constant acceleration (the 4 Kinematics equations). o Be able to use the kinematics equations to solve problems in multiple contexts. S4P Solve problems for objects moving in a straight line with a constant acceleration. o This will use kinematics equations S4P Solve relative motion problems for constant velocities using vectors. o One and two dimensions (excluding the sine law and cosine law problems) S4P Solve vector problems for objects in equilibrium. o One dimension - example, a sign suspended by one or two ropes (tension and Fg) o Two dimensions example: S4P Calculate the forces acting on an object resting on an inclined plane. S4P Calculate the components of Fg exerted on an object resting on an inclined plane. S4P Solve problems with Ff for objects on a horizontal surface and on an inclined plane. o This includes Atwood Machines and overhanging masses S4P Solve problems using Fnet = ma where Fnet = Fapplied + Ffriction and using kinematics equations. S4P Perform an experiment to investigate forces acting on an object. o Not on exam, we did this in class. S4P Derive the impulse-momentum equation from Newton's second law. o

2 S4P Determine impulse from the area under a force-time graph. o S4P Experiment to illustrate the Law of Conservation of Momentum in one and two dimensions. o Not on exam, we did this in class. S4P Solve problems using the impulse-momentum equation and the Law of Conservation of Momentum. o o Collisions, Explosions, Inelastic, and Elastic Collisions (one and two dimensions) S4P Relate the impulse-momentum equation to real-life situations. o Be able to solve problems involving baseballs, bullets, football players, cars, etc. S4P Solve simple free-fall problems using the special equations for constant acceleration. o If we are talking straight free fall (y-values), we can use kinematics S4P Draw free-body diagrams for a projectile at various points along its path (with and without air resistance). o

3 S4P Calculate the horizontal and vertical components with respect to velocity and position of a projectile at various points along its path. o Vertical = Kinematics Equations o Horizontal = horizontal vx is constant S4P Solve problems for projectiles launched horizontally and at various angles to the horizontal to calculate maximum height, range, and overall time of flight of the projectile. o We did a lot of practice with this in our projectiles lab! S4P Explain qualitatively why an object moving at constant speed in a circle is accelerating toward the centre of the circle. o An object experiencing uniform circular motion is continuously accelerating. We call this centripetal acceleration because the object always points towards the center of the circular path. S4P Discuss the centrifugal effects with respect to Newton's laws. o There is a common misconception that an object moving in a circle has an outward force acting on it that is called a centrifugal or centre-fleeing force. o As an example, consider a person swinging a ball on the end of a string. If you have ever done this yourself, you known that you feel a force pulling outward on your hand. This misconception arises when this pull is interpreted as an outward centrifugal force pulling on the ball that is transmitted along the string to the hand. o This is not what is happening at all! To keep the ball moving a a circle, the person pulls inwardly on the ball. The ball then exerts an equal and opposite force on the hand (Newton s third law) and this is what your hand feels. The force on the ball is the one exerted inwardly on it by the person. o Think of what would happen if you let go of the string. If there were a centrifugal force acting, the ball would fly straight out along the radius of its motion. We know that this doesn t happen. The ball actually flies off on a tangent in the direction of the velocity that it had at the moment it was released because the inward force no longer is acting.

4 S4P Draw free-body diagrams of an object moving in uniform circular motion. o S4P Experiment to determine the mathematical relationship between period and frequency and one or more of the following: centripetal force, mass, and radius. o We did this in our Centripetal Motion Lab not on exam. S4P Derive an equation for the constant speed and acceleration of an object moving in a circle. S4P Solve problems for an object moving with a constant speed in a circle using 3 equations (a = v2/r, v = 2 pi r/t, and Fnet = ma) S4P Define work as the product of displacement and the component of force parallel to the displacement when the force is constant.

5 S4P Determine work from the area under the forceposition graph for any force. S4P Describe work as a transfer of energy. S4P Give examples of various forms of energy and describe qualitatively the means by which they can perform work. o Kinetic Energy o Gravitational Potential Energy o Elastic Potential Energy (springs) S4P Derive the equation for kinetic energy using W = FΔd(cosθ) and kinematics equations. S4P Derive the equation for gravitational potential energy near the surface of the Earth (Ep = mgh). S4P Experiment to determine Hooke's Law. S4P Derive an equation for the potential energy of a spring, using Hooke's Law and a force-displacement graph. S4P Solve problems related to the conservation of energy. o May involve circular motion Unit 2: Fields S4P-2-1 Identify and analyze issues pertaining to space exploration. o You wrote me a big lovely paper on this so it will not be on the exam. S4P-2-2 Describe planetary motion using Kepler s three laws. o Be able to describe all 3, not just calculating Kepler s constant. S4P-2-3 Outline Newton s Law of Universal Gravitation and solve problems using S4P-2-4 State the gravitational potential energy as the area under the force-separation curve and solve problems using S4P-2-5 Solve problems for the escape velocity of a spacecraft. Include: The Law of Conservation of Energy and binding energy for both objects on the surface and in orbit.

6 S4P-2-6 Compare the Law of Universal Gravitation with the weight (mg) of an object at various distances from the surface of the Earth and describe the gravitational field as S4P-2-7 Outline Newton s thought experiment regarding how an artificial satellite can be made to orbit the earth. o Fc = Fg o o Recall that this was not on the formula sheet for the test and will not be on the formula sheet for the exam. S4P-2-8 Use the Law of Universal Gravitation and circular motion to calculate the characteristic of the motion of a satellite. Include: orbital period, speed, altitude above a planetary surface, mass of the central body, and the location of geosynchronous satellites. S4P-2-9 Define microgravity as an environment in which the apparent weight of a system is smaller than its actual weight. S4P-2-10 Describe conditions under which microgravity can be produced. S4P-2-11 Outline the factors involved in the re-entry of an object into Earth s atmosphere. Include friction and g-forces. S4P-2-12 Describe qualitatively some of the technological challenges to exploring deep space. o Again, you did this in a lovely write up for me so it will not be on the exam. S4P-2-13 Compare and contrast the inverse square nature of gravitational and electric fields. o S4P-2-14 State Coulomb s Law and solve problems for more than one electric force acting on a charge. Include both one and two dimensions (this will involve some component tables!) o

7 S4P-2-15 Illustrate, using diagrams, how the charge distribution on two oppositely charged parallel plates results in a uniform field. S4P-2-16 Derive an equation for the electric potential energy between two oppositely charged parallel plates (Ee = q E Δd) S4P-2-17 Describe electric potential as the electric potential energy per unit charge S4P-2-18 Identify the unit of electric potential as the volt.

8 S4P-2-19 Define electric potential difference (voltage) and express the electric field between two oppositely charged parallel plates in terms of voltage and the separation between the plates ( Ɛ = ΔV d ) S4P-2-20 Solve problems for charges moving between or through parallel plates (Millikan s Experiment). o S4P-2-21 Use hand rules to describe the directional relationships between electric and magnetic fields and moving charges. o I will be very definitive with my directions (like on the test). S4P-2-22 Describe qualitatively various technologies that use electric and magnetic fields. o Cathode Ray Tube o Mass Spectrometer Unit 3: Electricity S4P-3-1 Describe the origin of conventional current and relate its direction to the electron flow in a conductor. o I = q/t S4P-3-2 Describe the historical development of Ohm s Law (Gray, Ohm, Joule, and Kierchoff). o Not on exam I think we ve done enough with this! o You will still need to know how to use Ohm s Law to solve problems S4P-3-3 Investigate the relationships among resistance and resistivity, length, cross-section, and temperature. Include:

9 S4P-3-4 Demonstrate the ability to construct circuits from schematic diagrams for series, parallel, and combined networks. Include correct placement of ammeters and voltmeters. S4P-3-5 Calculate the total resistance for resistors in series and resistors in parallel. S4P-3-6 Calculate the resistance, current, voltage, and power for series, parallel, and combined networks. Include: S4P-3-7 Define magnetic flux o Lesson 9 (Jun 7 th ) S4P-3-8 Demonstrate how a change in magnetic flux induces voltage. o Lesson 9 (Jun 7 th ) S4P-3-9 Calculate the magnitude of the induced voltage in coils using o Lesson 9 (Jun 7 th ) S4P-3-10 Outline Lenz s Law and apply to related problems. o Lesson 10 (Jun 8 th ) S4P-3-11 Describe the operation of an AC generator. o Lesson 11 (after test Jun 9 th & the following Monday) S4P-3-12 Graph voltage versus angle for the AC cycle. o Lesson 11 (after test Jun 9 th & the following Monday) S4P-3-13 Describe the operation of transformers o Lesson 11 (after test Jun 9 th & the following Monday) S4P-3-14 Solve problems using the transformer ratio of o Lesson 11 (after test Jun 9 th & the following Monday) S4P-3-15 Describe the generation, transmission, and distribution of electricity in Manitoba. Include: step-up and step-down transformers, power transfer, High Voltage Direct Current o I m thinking we probably won t get here

10 Exam Review Problem Set 1 (Mechanics) 1. The velocity-time graph below represents the motion of a car. Assume that north is positive. a) In which interval(s) is the velocity uniform? b) In which interval(s) is the acceleration uniform? c) How far has the car traveled after i) 11 s? ii) 25 s? d) How far did the car travel in the 13 th second? e) What is the acceleration i) in the first 5.0 s? ii) from t =11 s to t =14 s? f) What is the instantaneous acceleration at i) t =12.5 s? ii) t = 22 s?

11 2. A ball rolls along the floor, up a sloping board, and then back down the board and across the floor again. The graph below represents the motion. a) At what time is the ball at its highest point? b) What was the acceleration when the ball was i) rolling up the board? ii) rolling down the board? iii) at rest at the top point? c) How far up the board did the ball go? d) What was the total displacement of the ball over the 9.0 s trip?

12 3. This graph describes the motion of a car. a) What is the instantaneous acceleration at i) t = 3.0 s? ii) t = 7.0 s? iii) t =11.0 s? b) How far does the car travel in the first i) 5.0 s? ii) 9.0 s? iii) 13.0 s? 4. When a batter hits a baseball its velocity is changed from 128 km / h due west to 136 km / h due east. (a) What is the change in speed? (b) What is the change in velocity? 5. A commuting student leaves home and drives to school at an average speed of 40 km / h. After 24 minutes he realizes that he has forgotten his homework and returns home to get it at the same average speed. It takes 10 minutes to find the report, after which the trip to school 40 km away to the east is resumed at the same speed as before. (a) What is the average speed for the entire trip? (b) What is the average velocity for the entire trip? 6. A Nissan Sentra can accelerate from 0 to 48 km / h in 3.6 s and from 0 to 96 km / h in 10.2 s. In addition, under constant acceleration from rest it crosses the 0.40 km marker at a speed of 130 km / h. (a) Calculate the average acceleration needed to reach 48 km / h. (b) Calculate the average acceleration during the time it takes to go from 48 km / h to 96 km / h. (c) What constant acceleration would be required to reach a speed of 130 km / h over the 0.40 km course when starting from rest?

13 7. A motorcycle traveling with a constant acceleration of 2.00 m / s 2 crosses a 100 m long bridge in 4.23 s. (a) What was the velocity at the beginning of the bridge? (b) What was the velocity at the end of the bridge? 8. A Lufthansa A320 accelerates from rest to liftoff speed of 73.7 m / s in 27.1 s. Each of the plane s two jet engines provides a forward force (thrust) of 111 kn. (a) What is the mass of the plane? (b) How far does the plane travel down the runway before liftoff? 9. A boat is traveling in a river with a current of 3.0 km / h. The boat is capable of traveling at 10.0 km / h in still water. (a) How long will it take the boat to travel 7.0 km upstream? (b) How long will it take to travel 7.0 km downstream? 10. A small airplane flies with a speed relative to the ground (ground speed) of 208 km / h in a direction 18 E of N. If the plane is headed due north and the deviation from that direction is due to a crosswind blowing from west to east, what is the speed of the wind? 11. A small airplane has a cruising speed of 260 km / h in still air. The pilot heads the plane in an easterly direction on a day when the wind is blowing at 25 km / h in a direction 60 N of E. In what direction will the plane move and what will be its ground speed? 12. A boat capable of making 9.0 km / h in still water is used to cross a river flowing at a speed of 4.0 km / h. (a) At what angle must the boat be directed so that its motion will be straight across the river? (b) What is its resultant speed relative to the shore? 13. A glass cube rests on a glass incline making an angle θ with the horizontal. The coefficient of friction between the cube and the incline is Find the maximum angle θ for the cube to remain at rest. 14. A load of 250 kg is supported by two steel cables, as shown below. Find the tensions in the cables.

14 15. A 50 kg traffic light is suspended above an intersection by two steel cables, as shown below. Determine the tension in the cables. 16. Suppose that the weight w 2 in the diagram below is 400 N. What must be the values of the weights w 1 and w 3 so that the entire system remains in equilibrium? 17. Two air-track gliders m 1 and m 2 are joined together with a light string as shown below. A constant horizontal force of 4.0 N to the right is applied to mass m 2. (a) If m 1 =1.5 kg and m 2 = 0.50 kg, what is the acceleration of the gliders? (b) What is the tension in the cord joining them?

15 18. An 8.0 kg mass rests on an inclined frictionless surface as shown below. A light string runs parallel to the surface from the mass over a light, frictionless pulley to a 3.6 kg mass. Find (a) the acceleration of the masses and (b) the tension in the string. 19. A 9.75 kg lead brick rests on a level wooden table. If a force of 46.4 N is required to slide the brick across the table at a constant speed, what is the coefficient of friction? 20. A 5.00 kg concrete block rests on a level table. The coefficient of friction between the block and the table is A 4.00 kg weight is attached to the block by a string of negligible mass passed over a light, frictionless pulley as shown below. What is the acceleration of the block when the 4.00 kg weight is released? 21. A 5.00 kg concrete block rests on a level table. The coefficient of friction between the block and the table is A 4.00 kg weight is attached to the block by a string of negligible mass passed over a light, frictionless pulley as shown above. If the acceleration of the block is measured to be 1.00 m / s 2, what is the coefficient of friction between the block and the table?

16 22. A crate starts from rest and slides 8.35 m down a ramp. When it reaches the bottom it is traveling at a speed of 5.25 m / s. If the ramp makes an angle of 20 with the horizontal, what is the coefficient of friction between the crate and the ramp? 23. A 10.0 kg block is placed on a frictionless inclined plane and connected to a 5.0 kg block as shown below. (a) What would the angle θ have to be for the blocks to remain motionless? (b) What would be the acceleration of the blocks if θ = 37? 24. What minimum force is required to drag a carton of books across the floor at constant speed if the force is applied at an angle of 45 to the horizontal? Take the mass of the carton as 40 kg and the coefficient of friction as Two blocks are connected by a light string passing over a pulley as shown below. The inclined surfaces are frictionless and the effects of the pulley can be ignored. If the values are mass m 2 = m 1 =1.00 kg, θ 1 = 46, and θ 2 = 34, what is the acceleration of the blocks?

17 26. A kg glider on a level air track is joined by strings to two hanging masses as shown below. The strings have negligible mass and pass over light, frictionless pulleys. (a) Find the acceleration of the masses and (b) the tension in the strings when the air flow is turned off and the coefficient of friction between the glider and the track is A kg baseball is pitched at 42 m / s. The batter hits it horizontally to the pitcher at 58 m / s. a) Find the change in momentum of the ball. b) If the ball and bat were in contact s, what would be the average force while they touched? 28. A 550 kg car traveling at 24.0 m / s collides head-on with a 680 kg pickup truck. Both vehicles come to a complete stop upon impact. a) What is the momentum of the car before the collision? b) What is the change in momentum of the car? c) What is the change in momentum of the truck? d) What is the velocity of the truck before the collision? 29. A 50.0 g projectile is launched with a horizontal velocity of 647 m / s from a 4.65 kg launcher moving in the same direction at 2.0 m / s. What is the velocity of the launcher after the projectile is launched? 30. Two lab carts are pushed together with a spring mechanism compressed between them. Upon release, the 5.0 kg cart repels one way with a velocity of 0.12 m / s while the 2.0 kg cart goes in the opposite direction. What velocity does it have? 31. A 12.0 g rubber bullet travels at a velocity of 150 m / s, hits a stationary 8.5 kg concrete block resting on a frictionless surface, and ricochets in the opposite direction with a velocity of 100 m / s. How fast will the concrete block be moving?

18 32. A pellet of mass 5.0 g is fired from a heavy gun whose barrel is 100 cm long. The force on the pellet while it is in the barrel is given by the graph below. What is the velocity of the pellet as it leaves the barrel? 33. A cannonball is dropped from the top of a building. If the point of release is 32.0 m above the ground, what is the speed of the cannonball just before it strikes the ground? 34. A ball is thrown straight up so that it reaches a height of 25 m. How fast was it going when it was 5 m high? 35. A cougar leaps horizontally from the top of a cliff with an initial velocity of 8.25 m / s. The cliff is 6.43 m tall. (a) Sketch the path of the cougar. (b) What are the magnitude and the direction of the velocity when the cougar is halfway to the ground? 36. A ball thrown horizontally from a 13 m high building strikes the ground 5.0 m from the building. With what velocity was the ball thrown? 37. A ball is thrown upward from a platform 5.2 m high with a speed of 15 m / s at an angle of 40 from the horizontal. What is the magnitude of its velocity when it hits the ground? 38. What is the centripetal acceleration of an automobile driving at 40 km / h on a circular track of radius 20 m? 39. Jupiter s moon Europa has an average orbital radius of m and a period of 85.2 h. Calculate the magnitude of (a) its average orbital speed, and (b) the centripetal acceleration of Europa. 40. Calculate the centripetal force on a 2000 kg automobile rounding a curve of 175 m radius at a speed of 50 km / h. 41. An electron with mass kg moves with a speed of m / s in a circle of 2.85 cm radius under the influence of a magnetic field. A proton of mass kg,

19 moving in the same plane with the same speed, experiences the same centripetal force. What is the radius of the proton s orbit? 42. A stunt pilot in an airplane diving vertically downward at a speed of 220 km / h turns vertically upward by following an approximately semicircular path with a radius of 180 m as shown below. (a) How many g s does the pilot experience due to his motion alone? (b) By what factor does the pilot s weight appear to increase at the bottom of the dive? 43. What is the maximum speed with which a 1000 kg car can round a turn of radius 85 m on a flat road if the coefficient of friction between tires and road is 0.60? Is this result independent of the mass of the car? 44. A 50 kg sled is pulled 20 m over the ice at a constant speed. The coefficient of friction between sled and ice is (a) What is the frictional force? (b) how much work is done in pulling the sled the 20 m? 45. (a) How much work is needed to push a 132 kg packing crate a distance of 2.65 m up a frictionless inclined plane that makes an angle of 20 with the horizontal? (b) How much work would be required to move the crate the same distance if the coefficient of friction were 0.20? 46. (a) How much work is required to increase the speed of a 1200 kg automobile from 10 km / h to 30 km / h? (b) How much work is required to further increase the speed by the same amount, this time from 30 km / h to 50 km / h? Neglect the effects of friction.

20 47. A block of mass m = 1250 g is released from rest and slides down a frictionless track of height h = 45.2 cm. At the bottom of the track the block slides freely along a horizontal table until it hits a spring attached to a heavy, immovable wall as shown below. The spring compressed by 3.24 cm at the maximum compression. What is the value of the spring constant k? 48. A 500 kg roller coaster starts from rest at point A and rolls freely (no friction) to point B where the brakes are applied and it slides along horizontally with a frictional force of 440 N. How far does the coaster slide past point B before coming to rest? 49. A stone thrown downward with a speed of 15.7 m / s from a height of 12.7 m above the ground has a kinetic energy of 293 J when it is 1.29 m above the ground. What is the mass of the stone? 50. A 40 kg child sits in a swing suspended with 2.5 m long ropes. The swing is held aside so that the ropes make an angle of 15 with the vertical. Use conservation of energy to determine the speed the child will have at the bottom of the arc when she is let go.

21 Exam Review Problem Set 2 (Fields) 1. Calculate the distance from the sun to Saturn, given the information that Saturn s period of revolution about the sun is years. 2. Use the known period of 27.3 days for the motion of the moon about the earth and the distance from the earth to the moon is m to calculate the radius of the orbit of an earth satellite that stays above the same point on the equator. 3. Compute the gravitational force between the sun M = kg ( m = kg, r = 19.2 AU ). ( ) and the planet Uranus 4. Calculate the mass of Jupiter from the knowledge that its satellite Io orbits at an average distance of km from its center with an orbital period of 42.5 h. 5. Calculate the orbital period of Venus from knowledge of G, the mass of the sun M = kg ( ), and the Venusian orbit radius of m. 6. Calculate the mass of the sun from the radius of the earth s orbit ( m), the earth s period in its orbit, and the gravitational constant G. 7. Assume that the orbit of the moon about the earth is a perfect circle with a center-to-center distance form earth to moon of m. (a) What is the gravitational force between the earth and the moon? (b) What is the speed of the moon in its orbit? Give your answer in meters per second. 8. An astronaut weighing 700 N on earth travels to the planet Mars. What does the astronaut weigh on Mars? (The mass of Mars is kg. The radius of Mars is m.) 9. A point charge of +6.3 µc is located 0.15 m from a second point charge of 4.8 µc. What are the magnitude and direction of the force on each charge? 10. Two charges of equal magnitude exert an attractive force of N on each other. If the magnitude of each charge is 2.0 µc, how far apart are the charges? 11. Two charged Styrofoam balls are moved so that the force between them becomes twelve times greater than it was originally. What is the ratio of their new separation to their original separation?

22 12. Two point charges of magnitude +9.0 µc are separated by a distance 30.0 cm. A third charge of equal magnitude and opposite sign is placed midway between the two positive charges. a) What is the net electrostatic force on the end charges? b) What is the net electrostatic force on the middle charge? 13. Three equal charges are placed at the corners of an equilateral triangle 0.50 m on a side. What are the magnitude and the direction of the force on each charge if the charges are 3.7 nc? 14. What is the electric field strength E at a point m from a point charge of µc? 15. A proton of charge q = C is placed in a region of uniform electric field with field strength ε = N / C. What is the electric force on the proton? 16. A proton accelerates from rest to m / s in s in a uniform electric field E. What is the magnitude of the electric field? (The proton has a mass m p = kg and a charge q = C.) 17. A charge of C is located at the point x = m, y = 0. A second charge of C is located at x = 0.10 m, y = 0. What are the magnitude and the direction of the electric field at (a) the point x = 0, y = 0 and (b) the point x = 0, y = m? 18. What is the electric potential at a point 0.45 m away from a point charge of 2.5 mc? 19. If J of work are required to move 13.7 µc of charge from one point to another, what is the electric potential difference between the two points? 20. A proton of mass m p = kg and charge q = C is accelerated from rest through an electric potential of 300 kv. What is its final velocity? 21. How much work is required to move an electron m through a uniform electric field of 7.65 V / m? 22. Alpha particles from a particular radioactive source have a speed of m / s. How large a magnetic field is required to bend the path of the particles into a circle of m radius? An alpha particle has a mass of kg and a charge of C. 23. A proton of charge C and mass kg is introduced into a region of B =1.15 T with an initial velocity of m / s perpendicular to B. What is the radius of the proton s path?

23 24. Suppose the electric field between the electric plates in the mass spectrometer shown below is V / m and the magnetic fields B = B = 0.75 T. The source contains boron isotopes of mass numbers 10 and 11 (to get their masses, multiply by kg ). How far apart are the lines formed by the singly charged ( +e ) ions of each type on the fluorescent film?

24 Exam Review Problem Set 3 (Electricity) 1. A 1.5 V dry cell is connected to a small light bulb with a resistance of 3.5 Ω. How much current flows through the bulb? 2. A current of 6.25 A flows through a microwave oven. If the resistance of the circuitry in the oven is 17.6 Ω, what is the voltage drop across the oven? 3. A 12.0 V storage battery is connected to three resistors, 6.75 Ω, 15.3 Ω, and 21.6 Ω respectively. The resistors are joined in series. (a) Draw a circuit diagram. (b) Calculate the total resistance. (c) What is the current? 4. You have three 12 Ω resistors. What is the combined resistance if they are (a) in series and (b) in parallel. (c) Draw a diagram for each. 5. A wire 6.24 m long with a diameter of 2.00 mm has a current of A when it is connected to a battery of five 1.50 V dry cells in series. Calculate the wire s (a) resistance (b) resistivity. 6. An 18.0 Ω, 9.0 Ω, and 6.0 Ω resistor are connected in parallel to a voltage source. A 4.00 A current flows through the 9.0 Ω resistor. (a) Draw the circuit diagram and calculate the equivalent resistance. (b) What is the voltage output of the source? (c) Calculate the current through the other resistors. 7. A 30.0 Ω resistance is connected in parallel to a 15.0 Ω resistor. These are joined in series to a 5.0 Ω resistor and a source with an emf of 30.0 V. (a) Draw a circuit diagram. Calculate (b) the total resistance (c) the voltage drop across each resistor (d) the current through each resistor. 8. Complete the chart of voltage, current, and resistance for the following circuit. Source R 1 R 2 R 3 R 4 R 5 R 6 V I R 2.0 A 5.0 Ω 3.5 V 1.5 A 4.0 V 1.0 A 2.0 Ω

25 9. A coil of 325 turns moving perpendicular to the flux in a uniform magnetic field experiences a change in flux of Wb in s. What is the induced emf? 10. A 20 cm diameter circular loop of wire is in a 0.60 T magnetic field. It is removed from the field in 0.10 s. What is the average induced emf? 11. If the resistance of the resistor in the diagram below is slowly increased, what is the direction of the current induced in the small circular loop inside the larger loop? 12. The moving rod in the diagram below is 12.0 cm long and moves with a speed of 15.0 cm / s. If the magnetic field is T, calculate the emf developed. 13. A step-up transformer is used on a 120 V line to provide a potential difference of 2400 V. If the primary coil has 75 turns, how many turns must the secondary coil have? 14. A 5:1 step-down transformer is connected to a 120 V ac source. The secondary circuit has a resistance of 15.0 Ω. (a) What is the potential difference across the secondary coil? (b) What is the current in the secondary coil? (c) How much power is dissipated in the secondary resistance? (d) What is the primary current?