Physical Science Final Flashcards

Front 1

In science, an educated guess is

Back 1

hypothesis

Front 2

In science, facts

Back 2

may change

Front 3

Compared with the mass of a certain object on Earth, the mass of the same object on the moon is

Back 3

the same

Front 4

The gain in speed each second for a freely falling object (without air resistance) object is about

Back 4

10 m/s

Front 5

Which has zero acceleration? An object

Back 5

at rest
moving at a constant velocity
in mechanical equilibrium

Front 6

What is the acceleration of a car that maintains a constant velocity of 100 km/h for 10s

Back 6

0

Front 7

If a freely falling ( without air resistance) object were somehow equipped with an odometer to measure the distance it travels, then the amount of distance it travels each succeeding second would be

Back 7

greater than the second before

Front 8

One object has twice as much mass as another object, and also has twice as much

Back 8

inertia

Front 9

The scientist to first introduce the concept of inertia was

Back 9

Galileo

Front 10

A kilogram is a measure of an object's

Back 10

mass

Front 11

An object travels 8 m in one second of travel, 8 m again during the next second of travel, and 8 m again during the following second. It's acceleration in meters per second is

Back 11

0

Front 12

A 2-kg mass at the Earth's surface weighs about

Back 12

20 N

Front 13

It takes 8 s for a stone to fall to the bottom of a mine shaft. Disregarding air resistance, how deep is the shaft?

Back 13

about 320 m

Front 14

A 500-kg bear grasping a vertical tree slides down at constant velocity. The friction force between the tree and the bear is

Back 14

5000 N

Front 15

A pot falls from a ledge and hits the ground 80 m below. Neglecting air resistance, the speed with which it hits the ground is about

Back 15

40 m/s

Front 16

A 20-N falling object encounters 6-N of air resistance. The magnitude of the net force on the object is

Back 16

14 N

Front 17

A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper is jerked quickly. This best demonstrates that

Back 17

the milk carton has inertia

Front 18

A skydiver, who weighs 400 N, reaches terminal velocity of 90 km/h. The air resistance on the diver is then

Back 18

400 N

Front 19

When a falling object has reached its terminal velocity, its aceleleration is

Back 19

0

Front 20

A heavy object and a light object are dropped at the same time from rest in a vacuum. The heavier object reaches the ground

Back 20

at the same time as the lighter object

Front 21

A player hits a ball with a bat. The action force is the impact of the bat against the ball. The reaction to this force is the

Back 21

force of the ball against the bat

Front 22

A car has a mass of 2000 kg and accelerates at 3m/s/s. What is the magnitude of the force exerted on the car?

Back 22

6000 N

Front 23

A skydiver steps from a helicopter and falls for 5 s before reaching her terminal velocity. During this 5 s interval, her acceleration

Back 23

decreases

Front 24

Careful: On the surface of Jupiter, where the acceleration dur to gravity is about 3 times that of Earth, a 100 kg rock would have a mass of about

Back 24

100 kg

Front 25

A bag of groceries has a mass of 15 kg and a weight of about

Back 25

150 N

Front 26

According to Newton's law of inertia, the result of walking much of the day is similar to tightening the head of a hammer when its handle hits a solid surface so that we should be a little bit shorter in the

Back 26

evening

Front 27

A 5 kg block is pushed across a horizontal force os 20 N against a friction force of 10 N. The acceleration of the block in meters per second per second is

Back 27

2

Front 28

On the surface os Jupiter, where the acceleration due to gravity is about 3 times of Earth, a 100 kg rock would have a weight of about

Back 28

3000 N

Front 29

If you are carrying a heavy bag of groceries and bang your hand against the wall, the concept that most explains why your hand is hurt is

Back 29

inertia

Front 30

An object is raised above the ground gaining a certain amount of potential energy. If the same object is raised twice as high, it gains

Back 30

twice as much potential energy

Front 31

A freight train rolls along a track with considerable momentum. If it rolls at the twice the velocity but has no change in mass, the momentum is

Back 31

doubled

Front 32

Which of the following has the most momentum

Back 32

a marble rolling across the floor

Front 33

If you push an object four times as far while applying the same force, you do

Back 33

four times as much work

Front 34

When you are in the way of a fast moving object and can't get out of the way, you will suffer a smaller force of impact if you can decrease its momentum over a

Back 34

longer time

Front 35

An object that has kinetic energy must be

Back 35

moving

Front 36

A car moves twice as fast as another identical car with identical mass. Compared to the slower car, the faster car has

Back 36

4 times the KE

Front 37

A ball is moving at 4 m/s and has a momentum of 24 kg m/s. What is the balls mass

Back 37

6 kg

Front 38

A moving object has

Back 38

speed
velocity
momentum
energy

Front 39

A piece of putty moving with 1 unit of momentum strikes and sticks to a heavy bowling ball that is initally at rest. After the putty sticks to the ball, both move with a combined momentum of

Back 39

1 unit

Front 40

A 4 kg mass is held 5 m above the ground. What is the approximate potential energy of the mass with respect to the ground?

Back 40

200 J

Front 41

A car moving at 50 km/h skids 25 m with locked brakes. How far will the car skid with locked brakes if it is traveling at 100 km/h?

Back 41

100 m

Front 42

A popular swinging balls apparatus consists of an aligned row of identical steel balls that are suspended by strings so they barely touch each other. When two balls are lifted from one end and released, they strike the row and the two balls pop out from the other end. IF instead one ball popped out with twice the speed of the two, this would be a violation of conservation of

Back 42

energy

Front 43

A positive ion has more

Back 43

protons than electrons

Front 44

A main difference between gravitational and electric forces is that electrical forces

Back 44

repel or attract

Front 45

The electrical force between charges is strongest when the charges are

Back 45

close together

Front 46

Charge carriers in a metal are electrons rather than protons because electrons are

Back 46

loosely bound

Front 47

A charged balloon neatly illustrates that something can have a great amount of

Back 47

voltage and a small potential energy

Front 48

An ampere is a unit of electrical

Back 48

current

Front 49

the current in a 100 W bulb connected to a 120 V source is

Back 49

.83 A

Front 50

The current through a 10 ohm resistor connected to a 120 V power supply is

Back 50

12 A

Front 51

The electric power of a lamp that carries 2 A at 120 V is

Back 51

240 W

Front 52

As more lamps are put into a series circuit, the overall current in the power source

Back 52

decreases

Front 53

As more lamps are put into a parellel circuit, the overall current in the power source

Back 53

increases

Front 54

Which is more dangerous, touching a faulty, underground 110 V light fixture or a Van de Graaff generator charged to 100,000 V? Touching the

Back 54

light fixture

Front 55

Rub electrons from your hair with a comb and the comb becomes

Back 55

negatively charged

Front 56

The source of all magnetism is

Back 56

moving electric charges

Front 57

Like kinds of magnetic poles repel while unlike kinds of magnetic poles

Back 57

attract

Front 58

Magnetism is due to the motion of electrons as they

Back 58

move around the nucleus and spin on their axes

Front 59

In terms of the way they are constructed, an electric motor and electric generator are

Back 59

very similar devices

Front 60

When there is a change in the magnetic field in a closed loop of wire,

Back 60

a voltage is induced in the wire
current is made to flow in the loop of wire
electromagnetic induction occurs

Front 61

Voltage can be induced in a wire by

Back 61

moving the wire near a magnet
moving a magnet near the wire
changing the current in a nearby wire

Front 62

A device that converts electrical energy to mechanical energy is a

Back 62

motor

Front 63

Transformers use ac so there will be the required

Back 63

change in magnetic field for operation

Front 64

The voltage across the primary terminals of a transformer is 110 V. The primary has 50 loops and the secondary has 100 loops. The voltage the transformer puts out it

Back 64

220 V

Front 65

Four amps of current exist in the primary coil of a transformer. The voltage across the primary coil is 110 V. What is the power output of the secondary coil?

Back 65

440 W

Front 66

A certain transformer doubles input voltage. If the primary coil has 20 A of current, then the current in the secondary coil is

Back 66

10 A

Front 67

Where does most rainfall on the earth finally end up before becoming rain again?

Back 67

the oceans

Front 68

What is an advantage of using chlorine gas to disinfect drinking water supplies?

Back 68

it provides residual protection against harmful bacteria

Front 69

Why is it important to conserve fresh water?

Back 69

there is little fresh water available to us on the planet

as the human population grows, so does our need for fresh water

it is expensive to purify water for drinking

Front 70

How are the disinfecting properties os ultraviolet light and ozone similar to each other?

Back 70

neither provides residual protection against harmful bacteria

Front 71

In wastewater treatment, we try to allow aerobic bacteria to predominate. Aerobic bacteria are those that

Back 71

do need oxygen in order to live

Front 72

of the total amount of water contained in the earth, how much of it is readily available as a source of fresh water supply?

Back 72

less than 1%

Front 73

the natural circulation of water in nature - from the oceans to the air then to the ground then to the oceans and then to the atmosphere is called the

Back 73

hydrologic cycle

Front 74

Solids removed from wastewater treatment can be used as

Back 74

incinerator fuel
landfill
fertilizer or soil conditioner

Front 75

most of the earths fresh water is located in

Back 75

polar ice caps and glaciers

Front 76

raw sewage is comprised mainly of water. on the average, how much water is in raw untreated sewage?

Back 76

99.9%

Front 77

evaporation from the oceans produces clouds that precipitate fresh water rather than saltwater because

Back 77

evaporation produces nearly pure water vapor

Front 78

a treatment chemical that is added to many municipal water supplies for the purpose of aiding and enhancing dental hygeine is

Back 78

fluoride

Front 79

in wastewater treatment, we are compressing the natural treatment processes from nature in both

Back 79

time and space

Front 80

some thunderstorms supercells will spawn tornadoes while others, even under similar conditions, will not. The reason for this phenomenon cannot yet be fully explained by meterological scientists and researchers.

Back 80

true

Front 81

tornadoes are most common in a region known as tornado alley which is located

Back 81

over the central US

Front 82

when a funnel cloud touches the ground it becomes a

Back 82

tornado

Front 83

a power line with a resistance of 2 ohms has a current of 80 A in it. The power dissipated in the line is

Back 83

12,800 W

Front 84

A 60 W light bulb and a 100 W light bulb are each connected to a 120 V outlet. Which light bulb has more current in it>

Back 84

the 100 W bulb

Front 85

According to Newtin, the greater the masses of interacting objects, the...

Back 85

greater the gravitational force between them

Front 86

If the mass of the Earth somehow increased with no change in radius, your weight would

Back 86

increase also

Front 87

Inside a freely falling elevator, there would be no

Back 87

apparent weight for you

Front 88

If the radius of the Earth somehow decreased with no change in mass, your weight would

Back 88

increase

Front 89

Two objects move toward each other because of gravity. As the objects get closer and closer, the force between them

Back 89

increases

Front 90

The reason the moon does not crash into the earth in that

Back 90

the moon has sufficient tangential velocity

Front 91

How far must one travel to get away from the earth's gravitational field>

Back 91

Forget it; you can't travel far enough

Front 92

A stone is thrown horizontally from the top of a cliff. One second after it has left your hand its vertical distance below the point where it left your hand is

Back 92

5 m

Front 93

An Earth satellite is simply a projectile freely falling around the earth

Back 93

true

Front 94

a bullet fired horizontally hits the ground in .5 seconds. If it had been fired with twice the speed in the same direction, it would have hit the ground in

Back 94

.5 seconds

Front 95

Earth satellites are typically more than 100km high so as to be above the earth's

Back 95

atmosphere

Front 96

A satellite near the earth makes a full circle in about an hour and a half. How long would a satellite located as far away as the moon take to orbit the earth?

Back 96

about 28 days

Front 97

communications and weather satellites always appear at the same place in the sky. This is because the satellites are

Back 97

rotating the earth once every 24 hours

Front 98

a dam is thicker at the bottom than the top because

Back 98

the pressure of the water is greater with increasing depth

Front 99

One liter of water has a mass of

Back 99

1 kg

Front 100

a completely submerged object always displaces its own

Back 100

volume of fluid

Front 101

when an object is immersed in a liquid, it is buoyed up by

Back 101

a force equal to the weight of the fluid it displaced

Front 102

a lobster crawls onto a bathroom scale submerged at the bottom of the ocean. compared to its weight above the surface, the lobster will have an apparent weight on the underwater bathroom scale that is

Back 102

less

Front 103

buoyant force is greatest on a submerged

Back 103

same on each whether it be a cm^3 of aluminum or lead

Front 104

atmospheric pressure is caused by the

Back 104

weight of the atmosphere

Front 105

the air in this room has

Back 105

mass
weight
energy

Front 106

airplane flight is best illustrated by

Back 106

Bernoulli's principle

Front 107

an umbrella tends to move upwards on a windy day principally because

Back 107

air pressure is reduced over the curved top surface whih in effect exerts a force upward on the underside of the umbrella

Front 108

in a vacuum, an object has no

Back 108

buoyant force

Front 109

suspend a pair of ping pong balls from two strings so there is a small space bewteen the two and blow air through the space. Which way will they swing?

Back 109

towards each other

Front 110

A substance that heats up relatively quickly has a

Back 110

low heat capacity

Front 111

heat energy is measured in

Back 111

joules and calories

Front 112

ice tends to form at the

Back 112

surface of the water

Front 113

the reason why the white hot sparks that strike your skin from a 4th of July type sparkler don't harm you is because

Back 113

the energy per molecule is high but the total energy transfer is minimal

Front 114

the moderate temperatures of islands throughout the world has much to do with waters

Back 114

relatively high heat capacity

Front 115

before ice can form on the surface of bodies of water, all of the water must be

Back 115

4C

Front 116

blow on your hand with an open mouth and the air is warm. pucker your lips and your breath is

Back 116

cooler

Front 117

consider a sample of water at 0 degrees C. If the temperature is slightly increased, the volume of water

Back 117

contracts

Front 118

a substance can absorb heat energy in by the processes of

Back 118

conduction
convection
radiation

Front 119

if a volume of air is warmed it expands. If air expands it

Back 119

cools

Front 120

evaporation is a cooling process. condensation is a

Back 120

warming process

Front 121

we are warmed by condensation because water molecules in the air that strike our bodies

Back 121

give off some of their kinetic energy

Front 122

when heat is added to boiling water, the water temperature

Back 122

stays the same

Front 123

consider a steaming aluminum soda-pop can that contains a small amount of boiling water. When it is quickly inverted, the can is dramatically crushed by atmospheric pressure. this occurs because the pressure in the can is rapidly reduced by

Back 123

condensation in the can

Front 124

inreasing the temp of 50 grams of water by 10 degrees requires

Back 124

500 calories

Front 125

What is the planetary lineup for a solar eclipse?

Back 125

the moon is directly between the sun and the earth

Front 126

What is the planetary lineup for a lunar eclipse?

Back 126

the earth is directly between the moon and the sun and the earths shadow is cast on the moon

Front 127

What roles do nuclear fusion and gravity in stars play?

Back 127

nuclear fusion and gravity work together to keep the star together. Nuclear fusion pushes the limits of the star out and gravity hold it all togther. When the nuclear fusion begins to dwindle, slowly gravity takes more of a part and the star everntually collapses

Front 128

When the new moon arrives and you are on the noon side of the globe, can you see the new moon?

Back 128

no

Front 129

How often does the earth make a full rotation?

Back 129

every 24 hours

Front 130

How often does the moon rotate on its axis?

Back 130

about every 28 days

Front 131

In a lunar eclipse, what would you see? On the moon?

Back 131

from earth, you see the colors oranges and reds because the earths atmosphere refracts most of the colors, from the moon you would see all the sunsets and rises of the earth

Front 132

What is Polaris and where in the sky is it found?

Back 132

Polaris is the North Star and is located directly above the north pole

Front 133

When a star supernovas and becomes a black hole, does the mass of the star change significantly?

Back 133

no

Front 134

What different star colors correspond with different heat levels?

Back 134

cooler stars - red (red giants)
medium temperature stars - white
hot - bluish white

Front 135

What is a solar wind?

Back 135

auroras -- have to do with sun radiation