1. Science Standards Review:
Energy

2. S8P2. Students will be familiar with the forms and transformations of energy.
a. Explain energy transformation in terms of the Law of Conservation of Energy.

3. The law of conservation of energy states that:
Energy is never destroyed
Energy is never created
Energy may be transformed or converted from one form to another
Energy is constantly changing forms

4. b. Explain the relationship between potential and kinetic energy.
Energy of Motion
Depends on
Speed
Mass
More speed = more KE
More mass = more KE

5. Potential Energy
Energy of position (stored energy)
Gravitational PE depends on
Weight
Height
More weight = more PE
More height = more PE

7. c. Compare and contrast the different forms of energy (heat, light, electricity, mechanical motion, sound) and their characteristics.

8. Light (radiant)—is electromagnetic energy ex. Sunlight, X-rays,
Forms of Energy:
Heat (thermal)—the vibration and movement of the atoms and molecules within substances
ex. Atoms move faster in hot water vs. ice water
Light (radiant)—is electromagnetic energy
ex. Sunlight, X-rays,
microwaves, p.636
Electricity—energy of moving electrons, typically moving through a wire
ex. lightening

9. Sound—energy caused by an object’s vibrations
Mechanical Motion—is energy stored in a moving object or an object that can move
PE + KE = mechanical energy
ex. Wind, Jack in the Box

10. ex. Cells in our body store chemical energy
Chemical—energy stored in the bonds of atoms and molecules (is released during chemical changes when atoms are rearranged)
ex. Cells in our body store chemical energy
Nuclear—energy stored in the nucleus of an atom — the energy that
holds the nucleus together
ex. Nuclear power plants

11. d. Describe how heat can be transferred through matter by the collisions of atoms (conduction) or through space (radiation). In a liquid or gas, currents will facilitate the transfer of heat (convection).

12. Conduction is the transfer of energy through matter from particle to particle as they touch.
Transfer of heat energy from atom to atom
Most effective in solids.
Heat moves from warmer substances to cooler substances.

13. Convection
the transfer of thermal energy by the movement of a gas or liquid (a medium).
The circular motion caused by density differences that result from temperature differences are called convection currents.

14. Radiation
the transfer of thermal energy by
electromagnetic waves such as visible light
and infrared waves. (See p ).
This energy can be transferred through
particles of matter OR empty space!
Examples
Energy from the sun
Microwaves use radiation

15. Review Questions
Which of the following converts electrical
energy into mechanical?
A light switch B electric stove
C light bulb D electric fan

16. According to the Law of Conservation of Energy, if Sally throws a watermelon with 100 joules of energy off the roof of a building, how much energy should the watermelon have as it hits the ground?
200 joules B joules
C. 100 joules D. 0 Joules

17. When a rock is thrown straight up into the air, it reaches its highest point and briefly comes to a complete stop before it starts to fall back to the ground. Which is greatest at the point where the rock stops?
A. potential energy
B. kinetic energy
C. force due to gravity
D. friction

18. A house becomes warm after air circulates in the house
A house becomes warm after air circulates in the house. What type of heat transfer happens?
Conduction
Convection
Radiation

19. Why do we insulate our soda cans?
To keep heat in
To keep heat out
To keep cold in
To keep cold out

20. Where is kinetic energy the greatest?
A B C D
Where is potential energy the greatest?

21. Tonya drops a ball off a cliff as shown in the picture
Tonya drops a ball off a cliff as shown in the picture. Which position shows where the ball has the most kinetic energy and the least potential energy?
A) A
B) B
C) C

22. Bob sat by the pool too long and his skin began to burn
Bob sat by the pool too long and his skin began to burn. What type of heat transfer occurred to make him burn?
Conduction
Convection
Radiation

23. At which position in the pendulum swing is kinetic energy greatest?
a. A b. B
c. C d. D
At which position in the pendulum swing is potential energy the lowest?

24. What type of heat transfer is happening in the picture?
A. Heat to electrical
B. Chemical to mechanical
C. Mechanical to light
D. Heat to mechanical
What type of heat transfer is happening in the air around the candle?
Conduction
Convection
Radiation

25. A gasoline-powered vehicle goes up a hill from point X to point Y
A gasoline-powered vehicle goes up a hill from point X to point Y. What energy transformation must occur in the car’s engine?
A Chemical energy into mechanical energy
B Electrical energy into light energy
C Electrical energy into sound energy
D Mechanical energy into light energy

26. When walking along an asphalt street after sundown, a person often feels heat coming off the pavement. The heat is moving from the asphalt to the person by
A. Conduction B. convection
C. Expansion D. radiation
Heat, light, and electricity are all forms of
A. Atoms B. energy
C. Cells D. motion

27. The batteries in a flashlight make electricity using
A. chemical B. solar
C. heat D. mechanical
In the pictures below, the candle is heating the water in the tank. Which picture shows how the water will move as it gets hot?

28. My dog, Ralph, wears slippers on hot days because the pavement is hot on his feet. What type of heat transfer makes his feet hot?
Conduction
Convection
Radiation

29. S8P3. Students will investigate relationship between force, mass, and the motion of objects.
a. Determine the relationship between velocity and acceleration.

30. Velocity—
the speed of an object in a particular direction
velocity must include speed (distance over time) and direction!
ex. an airplane travels west at 600 km/h
if speed or direction changes the velocity changes

31. Practice:
Tom is traveling west at 50 miles per hour. Sally and her family are traveling south at 50 miles per hour. Do the cars have the same velocity? Why or why not?
Tom
Sally

32. Acceleration—
The rate at which velocity changes
An object accelerates if its speed or
direction changes
an increase in velocity is called positive
acceleration
a decrease in velocity is called negative
acceleration or deceleration
the faster the velocity changes, the greater
the acceleration

33. b. Demonstrate the effect of balanced and unbalanced forces on an object in terms of gravity, inertia, and friction.

34. Balanced Forces
Occur when the forces on an object
produce a net force of 0 Newtons (N)
Will not cause a change in the motion of a
moving object
Will not cause a nonmoving
object to start moving
ex. Hat on your head, bird’s nest

35. Unbalanced Forces
Occur when the net force on an object is
not 0 Newtons (N)
The forces are unbalanced
Produce a change in motion
Are necessary to start movement or
change movement
ex. kicking a ball

36. Decide whether the following pictures represent a balanced or unbalanced force

37. Yes, you really are attracted to your science book!
Gravity—
A force of attraction between objects due
to their masses
Law of Universal Gravity—all objects in the
universe attract each other through
gravitational force +
Yes, you really are attracted to your science book!

38. a. Recognize that every object exerts gravitational force on every other object and that the force exerted depends on how much mass the objects have and how far apart they are.

39. Gravity decreases as distance increases.
The more mass, the more
gravitational force

40. The tendency of objects to resist any changes in motion
Inertia—
The tendency of objects to resist any
changes in motion
The more mass the more inertia
More mass more inertia
Less mass less inertia

41. Friction—
A force that opposes motion between two
surfaces that are in contact
Can cause a moving object to slow down
and eventually stop
Caused by roughness of surfaces

42. c. Demonstrate the effect of simple machines (lever, inclined plane, pulley, wedge, screw, and wheel and axle) on work.

43. Inclined Plane—
A flat slanted surface
Less input force necessary, but must be exerted over a longer distance
Examples: ramps, stairs,

44. Wedge—
Device that is thick at one end and tapers to a thin edge at the other end (two inclined planes back to back)
The longer and thinner the wedge, the less input force is required (same as with the inclined plane)
Examples: End of an ax, knife, zipper,
Push pin

45. An inclined plane wrapped around a cylinder
Screw—
An inclined plane wrapped around a cylinder
The closer the threads, the greater the mechanical advantage (longer distance, but less input force needed)
Examples: Jar lid, bolts, faucets
The closer the threads the greater the mechanical advantage

46. Two circular objects fastened together that rotate about a common axis
Wheel and Axle—
Two circular objects fastened together that rotate about a common axis
The object with the larger diameter is the wheel and the object with the smaller diameter is the axle
Multiplies your force, but you must exert your force over a longer distance
Examples: door knobs, steering wheels, screw drivers
wheel
axle

47. 3 different classes (types) of levers 1) 1st Class Levers—
A rigid bar that pivots or rotates about a fixed point called a fulcrum
3 different classes (types) of levers
1) 1st Class Levers—
Fulcrum (pivot point) is located between the input and output force (the load).
Change the direction of the force (they can also change size or distance of the force)
Examples: Seesaw, scissors, pliers, catapult
Effort
Load
Effort
Fulcrum
Fulcrum
Output/load

48. The load is between the fulcrum and input force (effort)
2nd Class Levers—
The load is between the fulcrum and input force (effort)
Do not change the direction of the input force
You must exert less force over more distance
Examples: Bottle openers, wheelbarrows
Input force (effort)
fulcrum
load

49. The input force (effort) is between the fulcrum and the load
3rd Class Levers—
The input force (effort) is between the
fulcrum and the load
Do not change the direction of the input force
Does not multiply your input force (effort) but allows you to apply a lot of force over a shorter distance
Examples: Tweezers, Rake, baseball bat, Hammer

50. 1st Class– fulcrum in the middle
Remember FLE
1st Class– fulcrum in the middle
2nd Class– load is in the middle
3rd Class– Effort (input force) is in the middle
load
Input force (effort)
fulcrum
Output/load
effort
fulcrum

51. Pulley—
Grooved wheel with a rope
(or chain, or cable) wrapped around it
Can change the amount and direction of your input force
Fixed Pulleys—
A pulley attached to a structure
Does not change the amount of input force
Changes the direction of the input force
Example: flag pole, sail boat, elevators

52. Moveable Pulley—
A pulley attached to the object being moved
Does not change the direction of the force
Does increase your force—you use less force over more distance
Example: a crane

53. Pulley System (Block and Tackle)—
Combination of fixed and moveable pulleys
Changes the size and direction of the force you exert

54. Review Questions
Which characteristic of motion could change without changing the velocity of an object?
A the speed B the position
C the direction D the acceleration

55. What two forces are responsible for keeping Earth in orbit around the sun?
Gravity and friction
Gravity and inertia
c. Friction and inertia
d. Strong force and inertia
Which of the following represents the velocity of a moving object?

56. A spring scale is pulled downward and readings are recorded.
If the spring is pulled 3.5 cm, the spring scale should read
A 12 N. B 13 N.
C 14 N. D 15 N.

57. A ball is dropped from the top of a tall building
A ball is dropped from the top of a tall building. As the ball falls, the upward force of air resistance becomes equal to the downward pull of gravity. When these two forces become equal in magnitude, the ball will
A flatten due to the forces.
B fall at a constant speed.
C continue to speed up.
D slow to a stop.

58. What is the net force on the cart above?
A 50 N. B 150 N.
C 200 N. D 350 N.

59. This box will increase in speed
A downward and to the left.
B downward and to the right.
C upward and to the left.
D upward and to the right.

60. When you bend your arm at the elbow, the bones and muscles in your arm are acting as a system. What simple machine does this system represent?
A. inclined plane B. pulley
C. Wedge D. lever
Which simple machine is a pair of scissors?
A. wheel and axle
B. pulley
C. inclined plane
D. lever

61. On Earth, an astronaut has a mass of 140 kg
On Earth, an astronaut has a mass of 140 kg. When the astronaut goes into space, she
will have a mass of 140 kg, but will have less weight.
will have less mass and weight.
will have a mass of 140 kg, and have a weight of 140 kg.
will have less mass and a weight of 140 kg.

62. A person dives out of a nonmoving boat in the direction indicated by Arrow A. Which arrow shows the direction in which the boat would move?
A. Arrow A
B. Arrow B
C. Arrow C
D. Arrow D

63. Which term refers to the rate of change of motion?
A. Acceleration B. speed
C. Momentum D. velocity
The tendency for a body at rest to remain at rest is known as
A. inertia
B. torque
C. momentum
D. mass

64. Where should Melissa position the fulcrum in order to minimize the amount of force needed to lift the box?
Point A B. Point B
C. Point C D. Point D

65. Which force causes a moving object to slow and then stop?
A. Acceleration B. inertia
C. Friction D. lift

66. S8P4. Students will explore the wave nature of sound and electromagnetic radiation.
a. Identify the characteristics of electromagnetic and mechanical waves.

67. All are transverse waves
Electromagnetic Waves—
Waves that do not need a medium—a substance through which the wave can travel
All are transverse waves
Ex. light, microwaves, TV &Radio waves, X-rays
Mechanical Waves—
Waves that need a medium—a substance through which the wave can travel
Can be transverse or longitudinal
Ex. sound waves, ocean waves

68. b. Describe how the behavior of light waves is manipulated causing reflection, refraction diffraction, and absorption.

69. Reflection—
occurs when waves bounce off an object
We see objects as different colors when that color is reflected back at us
Ex.—A leaf appears green because it reflects green light

70. Absorption–
The transfer of energy carried by light to particles of matter
The farther light travels from its source the more it is absorbed by particles (this is why light becomes dimmer)

71. Refraction—
The bending of a wave as it passes from one medium to another
Light travels slower through matter causing light to bend

72. Diffraction—
The bending of waves around barriers or through openings
Amount of diffraction depends on wavelength and size of barrier or opening
Wavelength of light is small so it cannot bend very much

73. c. Explain how the human eye sees objects and colors in terms of wavelengths.

74. We see different wavelengths of visible light as different colors
Longest wavelengths are red
Shortest wavelengths are violet
ROYGBIV

75. d. Describe how the behavior of waves is affected by medium (such as air, water, solids).

76. Sound travels quickly though air Even faster through liquids
Sound through media—
Sound travels quickly though air
Even faster through liquids
Fastest through solids
Warmer objects will conduct sound faster
Why?
Particles move faster in warm object so they transfer the sound faster

77. e. Relate the properties of sound to everyday experiences.

78. Sound—
a longitudinal wave caused by vibrations and carried through a substance
has to travel through a medium

79. Doppler Effect—
Apparent change in the frequency of a sound caused by the motion of the listener or the source of the sound
The sound will have a higher pitch as it approaches
Will have a lower pitch as it leaves

80. Echo—
Reflected sound wave
Occur when sound bounces off a flat hard surface

81. f. Diagram the parts of the wave and explain how the parts are affected by changes in amplitude and pitch.

82. Parts of the wave—
Crest—the highest point of a transverse wave
Trough—the lowest point of a transverse wave
Wavelength—the distance from any point on one wave to an identical point on the next wave
Amplitude—the maximum distance that the particles of a wave vibrate from their rest position

83. wavelength
Crest
Amplitude
Rest Position
Trough

84. Remember:
AL PF
Amplitude/loudness Pitch/Frequency
The amplitude of a wave is related to
height.
The greater the amplitude the louder the
sound and the more energy it has.

85. This wave will sound loud
This wave will sound quiet
This wave will sound loud

86. Frequency—the number of waves produced in a given amount of time
The frequency of a wave determines pitch.
A wave with a high frequency has a high pitch.
A wave with a low frequency has a low pitch.

87. This wave would have a high pitch.
This wave would have a low pitch.

88. Review Questions
Which color reflects all colors of light?
A. black B. white
C. green D. red
When Marcia yelled from the top of a canyon, an echo was created. This happened because the sound waves of her voice bounced back from the canyon walls. Which property of waves occurred?
A. Diffraction B. reflection
C. Interference D. refraction

89. There is only one fish in the fishbowl below
There is only one fish in the fishbowl below. When Joseph looks down at the fish, the image he observes is closer to the surface than the actual location of the fish.
Which wave characteristic does Joseph’s observation demonstrate?
A. amplitude B. diffraction
C. reflection D. refraction

90. Why are light-colored clothes cooler to wear in the summer than dark-colored clothes?
A. Light-colored clothes let more air in.
B. Light-colored clothes prevent sweating.
C. Light colored clothes are not as heavy as dark-colored clothes.
D. Light-colored clothes reflect more light than dark-colored clothes.

91. A family is building an outdoor shower at their cottage by hanging a plastic container from a post, as shown above. The container will be exposed to full sunlight. What color should the container be to make the water as warm as possible?
A. White B. yellow
C. Black D. red

92. In old movies, people sometimes put their ear on a railroad track to see if a train is coming. This works because the iron rail
A. is heated by friction
B. carries sound better than air
C. is cooler than air
D. is connected directly to the train

93. Sound A has a shorter wavelength than Sound B
Sound A has a shorter wavelength than Sound B. This means that Sound A will
A. be louder than Sound B.
B. be softer than Sound B.
C. have a lower pitch than Sound B.
D. have a higher pitch than Sound B.

94. Sound can travel fastest through
A. Air B. metal
C. Water D. outer space

95. A. B. C. D.
Which wave has the highest frequency?
Which wave has the highest pitch?
Which wave has the softest sound?
Which wave has the loudest sound?

96. S8P5. Students will recognize characteristics of gravity, electricity, and magnetism as major kinds of forces acting in nature.
b. Demonstrate the advantages and disadvantages of series and parallel circuits and how they transfer energy.

97. Types of Circuits: Series and Parallel
Series Circuits—
All parts of the circuit are connected in a single loop
Only one path for charges to follow
All loads share the same current

98. Disadvantages
Only one pathway for moving charges
If there is a break in the circuit charges stop flowing
(ex. if one light blows all the lights go out)
Advantages
Burglar alarms use series circuits

99. Parallel Circuits—
Loads are connected side by side
Charges have more than one path on which they can travel
Loads do not have the same current (each light will shine at full brightness)
houses are wired in parallel

100. c. Investigate and explain that electric currents and magnets can exert force on each other.

101. Electric Current—
The rate at which charges pass a given point
Expressed in amperes (amps)

102. How an object becomes charged…
If it loses electrons it becomes positively charged
If it gains electrons it becomes negatively charged
Charged objects create electric force
Greater the charge, the greater the force
Closer the charges, the greater the force

103. Magnets-
Anything that attracts iron or things made of iron
Have two poles (strongest attraction here)
Exert force on each other (magnetic force)
Surrounded by magnetic field

104. Electromagnetism—
Interaction between electricity and magnetism
Electric currents produce a magnetic field

105. Review Questions
At which location is Earth’s magnetic field the strongest?
1 B. 2
C D. 4

106. In which circuit will the bulb light up?A. B. C. D.

107. Which best describes a parallel circuit?
A Electricity flows along one pathway.
B The flow of electricity comes from one source.
C Electricity flows along more than one pathway.
D The flow of electricity comes from more than one source

108. Three identical light bulbs are connected in parallel with a battery, as shown, and all are lit. If bulb I is unscrewed and removed, what will happen to the other two light bulbs?
A. Both will stay lit.
B. II will go out, but III will stay lit.
C. II will stay lit, but III will go out.
D. Both will go out.

109. The bulb in the electric circuit will NOT light because
A. the switch is too far away from the bulb
B. the bulb has to be larger
C. the wires are not long enough
D. there is no energy source

110. Which electromagnet will pick up the most paper clips?B. C. D.

111. Which diagram is a parallel circuit?B. C. D.