Science 8Th Grade Final Exam Study Guide

Front 1

What is motion?

Back 1

Process of changing position.

Front 2

What are reference points?

Back 2

Starting point you use to describe the motion or the position of an object.

Front 3

Define speed.

Back 3

The distance an object moves divided by the time it takes to move that distance.

Front 4

Be able to calculate speed and know the units involved.

Back 4

Distance divided by time. m/s, mph, f/s.

Front 5

What is velocity?

Back 5

Speed and the direction of a moving object.

Front 6

Be able to calculate velocity and know the units involved.

Back 6

Acceleration divide by time including direction.

Front 7

How is speed different from velocity?

Back 7

Velocity includes a direction.

Front 8

What is acceleration?

Back 8

Measure of the change in velocity during a period of time.

Front 9

Be able to calculate acceleration and know the units involved.

Back 9

acceleration=final speed-initial speed divided by total time.

Front 10

Know the difference between positive and negative acceleration.

Back 10

Positive-increasing. Negative-decreasing.

Front 11

Negative acceleration is also called.

Back 11

Deceleration.

Front 12

What is a force?

Back 12

A push or pull on an object.

Front 13

What is a contact force?

Back 13

A push or pull on one object by another object that is touching it.

Front 14

What is a noncontact force?

Back 14

A force that one object applies to another object without touching it.

Front 15

Forces have both __________ and __________.

Back 15

Strength and direction.

Front 16

What is the SI unit of force?

Back 16

Newtons.

Front 17

What is gravity?

Back 17

An attractive force that exist between all objects that have mass.

Front 18

What is friction?

Back 18

A contact force that resists the sliding motion of two surfaces that are touching.

Front 19

Describe static friction.

Back 19

Prevents surfaces from sliding past each other.

Front 20

Describe sliding friction.

Back 20

Opposes the motion of surfaces sliding past each other.

Front 21

Describe rolling friction.

Back 21

Friction with wheels.

Front 22

Describe fluid friction.

Back 22

Friction between a surface and a fluid.

Front 23

What is air resistance?

Back 23

Fluid friction between a surface and air.

Front 24

What two things cause friction?

Back 24

Microscopic dips and bumps and small electric charges that all objects have.

Front 25

How can you increase friction?

Back 25

Apply more force.

Front 26

How can you reduce friction?

Back 26

Using some kind of lubricant.

Front 27

What is a net force?

Back 27

The combination of all the forces acting on an object.

Front 28

How do you combine forces in the same direction? The opposite direction?

Back 28

Same direction- Opposite Direction- net force = zero

Front 29

What are balanced forces?

Back 29

Forces acting on an object that combine and form a net force of zero.

Front 30

How does motion affect balanced forces?

Back 30

It does not affect balanced forces.

Front 31

What are unbalanced forces?

Back 31

Forces acting on an object that combine and form a net force that is not zero.

Front 32

How does motion affect unbalanced forces?

Back 32

It moves them in the direction of that force.

Front 33

What is Newton’s 1st law of motion?

Back 33

If the net force on an object is zero, the motion of the object does not change.

Front 34

This law only applies to _________ forces acting on an object.

Back 34

Balanced.

Front 35

What is inertia?

Back 35

The tendency of an object to resist a change in its motion.

Front 36

Newton’s 1st Law is also called the Law of ________.

Back 36

Interia.

Front 37

What is Newton’s 2nd law?

Back 37

The acceleration of an object is equal to the net force acting on the object divided by the object’s mass.

Front 38

How do you calculate Newton’s 2nd Law?

Back 38

acceleration=net force/mass

Front 39

What is centripetal motion?

Back 39

Any motion in which an object is moving along a curved path.

Front 40

Examples of centripetal motion?

Back 40

The moon orbiting around earth.

Front 41

What is Newton’s 3rd Law of Motion?

Back 41

When one object exerts an equal force in the opposite direction on the first object.

Front 42

What is a force pair?

Back 42

The forces two objects apply to each other.

Front 43

What are the 2 forces in a force pair?

Back 43

Action and reaction.

Front 44

What is momentum?

Back 44

A measure of how hard it is to stop a moving object.

Front 45

How do you calculate momentum?

Back 45

momentum=mass x velocity.

Front 46

What is the Law of Conservation of Momentum?

Back 46

The total momentum of a group of objects stays the same unless outside forces act on the objects.

Front 47

What is energy?

Back 47

The ability to cause change.

Front 48

What is kinetic energy?

Back 48

Energy due to motion.

Front 49

What two things does kinetic energy depend on?

Back 49

Speed and mass.

Front 50

What is potential energy?

Back 50

Stored energy due to the interactions between objects or particles.

Front 51

What two thing does potential energy depend on?

Back 51

Height and weight.

Front 52

What is work?

Back 52

The transfer of energy that occurs when a force is applied over a distance.

Front 53

What is the formula for work?

Back 53

Force X distance = work

Front 54

What does work depend on?

Back 54

Force and distance.

Front 55

What units is energy measured in?

Back 55

Joules.

Front 56

What units is work measured in?

Back 56

Joules.

Front 57

What is mechanical energy? Give examples.

Back 57

The total energy of an object or group of objects due to large-scale motions and interactions. When a player shoots a basketball.

Front 58

What is sound energy? Give examples.

Back 58

The energy sound carries. Vibrating things emit sound

Front 59

What is thermal energy? Give examples.

Back 59

Energy due to the motion of particles that make up an object. A campfire.

Front 60

What is electric energy? Give examples.

Back 60

Energy that an electric current carries. Fans and dishwashers.

Front 61

What is radiant energy? Give examples.

Back 61

Energy that electromagnetic waves carry. Microwaves.

Front 62

What is nuclear energy? Give examples.

Back 62

Energy that is stored in the nucleus of an atom.

Front 63

What is the law of conservation of energy?

Back 63

Energy can be transformed from one form into another or transferred from one region to another, but energy cannot be created or destroyed.

Front 64

What is a wave?

Back 64

A disturbance that transfer energy from one place to another without transferring matter.

Front 65

Waves transfer ______ but not ______.

Back 65

Energy not matter.

Front 66

What is a mechanical wave?

Back 66

A wave that can travel only through matter.

Front 67

What states of matter can mechanical waves travel through? What can’t they travel through?

Back 67

Can travel through solids, liquids, and gases. Cannot travel through a vacuum.

Front 68

Explain transverse waves.

Back 68

A wave in which the disturbance is perpendicular to the direction the vace travels.

Front 69

What are crests? Troughs?

Back 69

Highest point of the transverse wave-crest. Lowest point of transverse-trough.

Front 70

What are longitudinal waves?

Back 70

A wave in which the disturbance is parallel to the direction the wave travels.

Front 71

What are compressions?

Back 71

Region of a longitudinal wave where the particles of the medium are closest together.

Front 72

What are rarefactions?

Back 72

The regions of a longitudinal wave where the particles of the medium are farthest apart.

Front 73

What is a vibration?

Back 73

A rapid back-and-forth motion that can occur in solids, liquids, or gases.

Front 74

Give examples of mechanical waves.

Back 74

Sound waves, water waves, and seismic waves.

Front 75

What are electromagnetic waves?

Back 75

A transverse wave that can travel through empty space and through matter.

Front 76

What is amplitude?

Back 76

The maximum distance a wave varies from its rest position.

Front 77

What is wavelength of a wave?

Back 77

The distance between one point on a wave and the nearest point just like it.

Front 78

What is the frequency of a wave?

Back 78

The number of wavelengths that pass by by a point each second.

Front 79

Be able to calculate wave speed.

Back 79

Wave speed=frequency X wavelength.

Front 80

Know what materials mechanical waves travel fastest in. Slowest?

Back 80

Fastests in solids. Slowest in gases.

Front 81

What is reflection?

Back 81

The bouncing of a wave off a surface.

Front 82

What is a refraction?

Back 82

The change in direction of a wave that occurs as the wave changes speed when moving from one medium to another.

Front 83

Know the purpose of the outer ear.

Back 83

The outer ear collects sounds.

Front 84

Know the purpose of the middle ear.

Back 84

The middle ear amplifies sound.

Front 85

Know the purpose of the inner ear.

Back 85

The brain interprets vibrations from the hair inside your ears.

Front 86

What is radiant energy?

Back 86

Energy carried by an electromagnetic wave.

Front 87

What provides most of Earth’s radiant energy?

Back 87

Sun.

Front 88

Most of the Sun’s energy is carried by _____________ waves.

Back 88

Visible light.

Front 89

What is the electromagnetic spectrum?

Back 89

The entire range of electromagnetic waves with different frequencies and wavelengths.