5th grade lesson on energy and motion.

1. Energy and the Motion of Objects
Forces and Motion Part 2
By Mrs. Burch 11/1/18
Teach gravity, friction,
and forces before
this lesson.

2. Energy is needed to put objects into motion, but
what is the scientific definition of energy?

3. Energy is the ability to do work.

4. There are different kinds of energy:
heat energy chemical energy
light energy electrical energy
sound energy kinetic energy
magnetic energy potential energy

5. The Law of Conservation of Energy states that the
total amount of energy remains the same in a
closed system.

6. What does “conservation” mean?

7. “Conservation” means the saving of
something. For example, to conserve water
means to save it instead of wasting it.

8. According to the Law of Conservation of Energy,
energy can neither be created nor destroyed, but can
be transformed, or changed, from one form to another.

9. For example, electrical energy can be
transformed to heat energy.

10. Light energy can be transformed to electrical
energy.

11. Motion (kinetic) energy can be transformed
to sound energy.

12. Chemical energy (chemical reaction) can be
transformed to heat, light, and sound energy.

13. What does this conservation of energy look
like?

14. Consider a bowling ball rolling down the
lane. It has energy in the form of motion.

15. What happens to this energy when the ball
hits the pins?

16. The energy from the bowling ball is transferred to the
pins. This gain in energy causes the pins to “go flying”.

17. None of the energy was destroyed or lost. It was just
transformed from a rolling motion to a pushing force.
Some of this motion energy was also transformed into
sound energy and even a little heat energy.

18. Another example of the Law of Conservation of
Energy is Newton’s cradle.
https://www.youtube.com/watch?v=8dgyPRA86K0

19. Over time, Newton’s cradle will come to a
complete stop. So, where does the energy go, if
it’s not possible for it to be destroyed?

20. Answer: Some of the motion energy will transform
into sound energy (you can hear the metal clacking
together) and some will transform into heat energy
(both in the metal and in the strings due to friction).

21. Now, let’s focus on potential and kinetic energy.
heat energy chemical energy
light energy electrical energy
sound energy kinetic energy
magnetic energy potential energy

22. What is potential energy?

23. The idea of potential energy goes all the way back
to the Greek philosopher Aristotle around 350 BC.
Statue of Aristotle

24. Potential energy is stored energy.

25. Examples of objects with potential energy:
A rubber band that is stretched. The more it is stretched, the more
potential energy it has.

26. A match may not appear to have any energy by
itself, but it does contain potential energy that can
be released.

27. The chemical energy stored in a match can be changed
into light and heat energy. The friction between
the match and the striking surface produces heat (this
heat is what starts the chemical reaction).

28. A ball sitting at the top of a ramp isn’t moving.
Even so, it has energy - potential energy.

29. It took energy to place the ball at the top of the
ramp. This energy is now stored in the ball.

30. This energy is equal to the amount of energy it
took to put it at the top.

31. Once the ball starts rolling, the potential energy is
steadily converted into kinetic energy.
https://youtu.be/tUmVqgBp06s

32. So, the potential energy is converted into kinetic
energy. But, what is kinetic energy?
Yeah, what iz dis
kinetic energy
stuff?

33. Kinetic energy is the energy of motion.

34. Kinetic energy is the energy of ______.

35. Kinetic energy is the energy of motion.

36. The kinetic energy of an object depends
on 2 things…

37. …the mass of the object and…
Which has more mass?

38. …its speed.

39. Quick review: The amount of kinetic energy an
object has depends on its mass and speed.

40. Quick review: The amount of kinetic energy an
object has depends on its mass and speed.

41. Let’s investigate how mass and speed are related
in kinetic energy…

42. Investigation: Work in teams to determine the
answer to the following question:

43. Question: What is the relationship between how quickly an
object’s motion can change, the mass of the object, and the
amount of force acting on it.
Materials: Scale to weigh the marbles
Ramp with rounded channel (6 ft. long)
Stopwatch or timer on iPad
1 heavy glass marble
1 light-weight glass marbles
1 BB
Data recording chart

44. Question: What is the relationship between how quickly an object’s
motion can change, the mass of the object, and the amount of force
acting on it.
Procedure:
1. Place a ping pong ball 1 inch in front of the bottom of the ramp.
2. Release the largest marble. Measure how far the ping
pong ball moves after the collision.
3. Repeat this procedure using the small marble. Measure.
4. Repeat using the BB. Measure.
5. Repeat steps 1-4, except replace the ping pong ball with a pool
ball. Be sure to record your measurements.

45. Discuss the results of the investigation as a class.
Question: What is the relationship between how quickly an object’s
motion can change, the mass of the object, and the amount of force
acting on it.

46. The relationship between the 3 is this: How quickly an
object’s motion is changed depends on the force
acting and the object’s mass. The greater the mass of
an object, the longer it takes to speed it up or slow it
down, a property of mass called “inertia”.

47. Based on what you know about the relationship
between mass and speed, consider the following…

48. Which would need more distance and time to
come to a complete stop?

49. Answer: The semi-truck. The heavier the object,
the more distance and time it needs to change its
motion.

50. Which would need more time and force to
speed up to 65 mph?

51. Answer: The semi-truck. The more mass an object
has, the more force required to change its motion.

52. Now, let’s get back to our earlier topic…

53. Remember that the ball was placed at the top of
the ramp and now has potential energy.

54. As the ball travels down the ramp, it gains speed and
kinetic energy. As the ball gains kinetic energy, it loses
potential energy.

55. Let’s take a look at a roller coaster…

56. As the car travels up the coaster, it is gaining potential energy.
It gets this energy from the motor that pulls the car up the
incline.
The car is gaining
potential energy
as it climbs.

57. At the highest point, the car has the most potential energy.

58. As the car starts down the incline, it gains kinetic energy and
loses potential energy.

59. At the bottom of the incline, the car has the most kinetic
energy and 0 potential energy.

60. As the car starts up the next incline, it starts to lose kinetic
energy and gain potential energy.

61. If you double the mass of an object, you double
the kinetic energy.

62. If you double the mass of an object, you double
the kinetic energy.
Science is
cool!

63. If you double the speed of an object, the kinetic
energy increases by four times.
more
speed
more
kinetic
energy
=

64. The word "kinetic" comes from the Greek word
"kinesis" which means “motion”.

65. The word "kinetic" comes from the Greek word
"kinesis" which means “motion”.
Doesn’t
everyone know
that?

66. Kinetic energy can be passed from one object to
another in the form of a collision.

67. When two objects bump into each other, this is called a
collision. In physics, a collision doesn't have to involve
an accident (like two cars crashing into each other), but
can be any event where two or more moving objects
exert forces on each other for a short period of time.
Examples:
One ball striking another on a pool table
A baseball bat hitting a ball
Your fingers striking the key on the keyboard

68. Quiz yourself:

69. What is the name of energy that is stored in
objects?

70. What is the name of energy that is stored in
objects?
Answer: potential energy

71. What is the energy of motion called?
Answer: kinetic energy

72. True or False? The faster an object is moving,
the more energy it possesses.

73. True or False? The faster an object is moving,
the more energy it possesses.
Answer: true

74. True or False? Energy can be transferred
from one moving object to another.

75. True or False? Energy can be transferred
from one moving object to another.
Answer: true

76. True or False? Kinetic energy can be
transformed into sound energy.

77. True or False? Kinetic energy can be
transformed into sound energy.
Answer: true

78. True or False? Kinetic energy can be
transformed into heat energy.

79. True or False? Kinetic energy can be
transformed into heat energy.
Answer: true

80. True or False? Energy that is spent
disappears and goes away.

81. True or False? Energy that is spent
disappears and goes away.
Answer: false

82. True or False? Energy from the Sun is
transferred to Earth through light and heat.

83. True or False? Energy from the Sun is
transferred to Earth through light and heat.
Answer: true

84. True or False? The Law of Conservation of
Energy states that energy can be created.

85. True or False? The Law of Conservation of
Energy states that energy can be created.
Answer: false. The law says energy
can neither be created nor
destroyed.

86. True or False? Objects with more mass
require more force to change their inertia.

87. True or False? Objects with more mass
require more force to change their inertia.
Answer: true

88. Good job!