Energy transfers

9.A bow stores 20 J of elastic potential energy before firing an arrow. After the arrow is fired, what is the total energy in the arrow's kinetic store and the thermal store of the surroundings combined?

10.Which of the following describes an energy transfer by heating?

11.When a pendulum swings, it eventually stops. Where does the energy go?

12.A battery-powered toy car moves across the floor. Which energy transfer pathway is primarily responsible for the car's movement?

13.A student investigates energy transfers using a toy car on a ramp. The car is released from rest at the top of the ramp and travels down. Which statement correctly describes the energy changes?

14.A 2 kg mass is lifted vertically through a height of 5 m. The gravitational field strength is 10 N/kg. How much gravitational potential energy is gained by the mass?

15.A student drops a ball from a height of 2 m. The ball has a mass of 0.5 kg. Ignoring air resistance, what is the kinetic energy of the ball just before it hits the ground? (g = 10 N/kg)

16.The diagram shows a roller coaster car at the top of a hill. It has 50,000 J of gravitational potential energy. As it descends to the bottom, 10,000 J of energy is transferred to the thermal energy store of the surroundings. What is the kinetic energy of the car at the bottom?

17.Which of the following is an example of energy transfer by radiation?

18.A student investigates the efficiency of a motor that lifts a mass. The motor does 200 J of electrical work, but only 150 J of gravitational potential energy is gained by the mass. What is the efficiency of the motor?

19.A pendulum swings from its highest point to its lowest point. At the highest point, the pendulum has 8 J of gravitational potential energy and 0 J of kinetic energy. Ignoring air resistance, what is the total energy of the pendulum at the lowest point?

20.A student uses a battery-powered fan. Which energy transfer pathway is primarily responsible for the fan blades moving?

21.What is the unit used to measure energy?

22.A student sets up the circuit shown. The ammeter reads 0.5 A and the bulb is lit. Which energy transfer pathway is taking place in the wires?

23.A ball is thrown upwards. At the highest point of its motion, which energy store is at a maximum?

25.A student investigates energy transfer using a toy car on a ramp. The car is released from rest at the top of the ramp and travels down. Which statement correctly describes the energy changes?

26.A pendulum swings from its highest point to its lowest point. At the highest point, the pendulum has 8 J of gravitational potential energy and 0 J of kinetic energy. What is the total energy of the pendulum at the lowest point?

27.The diagram shows a roller coaster car at the top of a hill. It has 50,000 J of gravitational potential energy. As it descends to the bottom, 10,000 J of energy is transferred to the thermal energy store of the surroundings due to friction. What is the kinetic energy of the car at the bottom?

29.In an experiment to measure the efficiency of a motor, a student measures the electrical energy input and the gravitational potential energy gained by a mass. Which additional measurement is needed to calculate efficiency?

30.Which of the following correctly states the principle of conservation of energy?

31.A bow stores 20 J of elastic potential energy before firing an arrow. After the arrow is fired, the arrow's kinetic energy store is 18 J. What is the most likely reason for the difference?

32.What does 'work done' mean in physics?

33.The diagram shows a roller coaster car at the top of a hill. It has 50,000 J of gravitational potential energy. As it descends to the bottom, 10,000 J of energy is transferred to the thermal energy store of the track and surroundings due to friction. What is the kinetic energy of the car at the bottom?

34.A pendulum swings from its highest point to its lowest point. At the highest point, the pendulum has 8 J of gravitational potential energy and 0 J of kinetic energy. Ignoring air resistance, what is the kinetic energy at the lowest point?

35.In an experiment to measure the efficiency of a motor, a student measures the electrical energy input and the gravitational potential energy gained by a mass. The student finds that the motor lifts a 2 kg mass through a height of 1.5 m using an electrical energy input of 40 J. The gravitational field strength is 10 N/kg. What is the efficiency of the motor?

36.A student investigates the energy transfers in a bouncing ball. The ball of mass 0.1 kg is dropped from a height of 2.0 m. It rebounds to a height of 1.6 m. The gravitational field strength is 10 N/kg. Calculate the energy lost to the surroundings during the bounce.

37.A student uses a joulemeter to measure the electrical energy supplied to a motor. The motor lifts a 0.5 kg mass through a height of 0.8 m. The joulemeter reads 5 J. The gravitational field strength is 10 N/kg. What is the efficiency of the motor?

38.A student sets up a simple pendulum. The bob has mass 0.2 kg. The student pulls the bob sideways so that it is 0.1 m higher than its lowest point, then releases it. The gravitational field strength is 10 N/kg. Ignoring air resistance, what is the maximum speed of the bob during its swing?

39.Which of the following is the correct unit for energy?

40.In an experiment to investigate energy transfer by heating, a student places a metal block on a tripod and heats it with a Bunsen burner. The student measures the temperature rise of the block using a thermometer. Which of the following would improve the accuracy of the experiment?

41.Energy can be created in a chemical reaction.

42.Which of the following is a pathway for energy transfer?

43.Select all the pathways for energy transfer. (Select all that apply)

44.Arrange the following energy transfers in the correct order for a pendulum starting from its highest point on the left.

45.A pendulum has 10 J of gravitational potential energy at its highest point. At the lowest point, its kinetic energy is measured to be 9.5 J. What is the most likely reason for this difference?

46.Match each energy store to its description.

47.Arrange the energy transfers in the correct order for a pendulum starting from its highest point on the left.

48.Which of the following are pathways for energy transfer? (Select all that apply)

49.A pendulum has 10 J of gravitational potential energy at its highest point. At the lowest point, its kinetic energy is measured to be 9.5 J. What is the most likely reason for the missing 0.5 J?

50.A student uses a battery-powered toy car on a rough surface. The car's battery transfers 50 J of electrical energy. The car's kinetic energy increases by 35 J, and the rest is transferred to the thermal energy store of the surroundings. Which statement is correct?

51.Complete the sentence: The principle of conservation of energy states that energy is never created or destroyed; it is only ________ from one energy store to another.

52.State what 'work done' means in physics.

53.Complete the sentences about the pendulum energy transfers.

54.A book on a shelf has 30 J of gravitational potential energy. It falls to the ground. Assuming no air resistance, how much kinetic energy does it have just before hitting the ground?

55.In practice, why is the kinetic energy of a falling object just before it hits the ground less than its initial gravitational potential energy?

56.State the principle of conservation of energy.

57.A 0.5 kg mass is lifted vertically through a height of 2 m. The gravitational field strength is 10 N/kg. How much gravitational potential energy is gained by the mass? (Answer in joules)

58.A student lifts a 2 kg mass vertically through a height of 3 m. The gravitational field strength is 10 N/kg. How much gravitational potential energy does the mass gain? (Give your answer in joules.)

59.Describe the energy transfers that take place when an arrow is fired from a bow.

60.Describe why a pendulum eventually stops swinging, even though the principle of conservation of energy says energy cannot be destroyed.

61.A book on a shelf has 30 J of gravitational potential energy. It falls to the ground. Assuming no air resistance, how much kinetic energy does it have just before hitting the ground?

62.A 0.5 kg mass is lifted vertically through a height of 2 m. The gravitational field strength is 10 N/kg. How much gravitational potential energy is gained by the mass? (Answer in joules)

63.A student lifts a 2 kg mass vertically through a height of 3 m. The gravitational field strength is 10 N/kg. How much gravitational potential energy does the mass gain? (Give your answer in joules.)