science test 2/27

Question 1

Centripetal force

Answer 1

a center-directed force that continuesly changed the diretion of an object – moves in a circle

Question 2

what was newtons law of univeral gravitation state

Answer 2

that every object in the universe attracts every other object

Question 3

gravitational force

Answer 3

an attraction force acts between any two masses

Question 4

what is the weekest gravitational force

Answer 4

gravity

Question 5

weak unclear force

Answer 5

attractive force that acts only over a short range

Question 6

strong nuclear force

Answer 6

a powerful force of attraction that only on the neutrons and protons in the nucleus, holding them together

Question 7

the weak nuclear force is involved in certain types _____ process

Answer 7

radioactive

Question 8

the strong nuclear forces overcomes the ___ force of the replusion that acts among the ___ in the nucleas

Answer 8

electric, protons

Question 9

what acts within in the nucleas to hold it together

Answer 9

the strong and weak nuclear force

Question 10

magenetic forces act ob ___ metals on the ___ of the magnets, and on ____ charges

Answer 10

certain, poles, moving

Question 11

objects with like charges

Answer 11

repel

Question 12

Objects with oppsite changes like positive and negative, they

Answer 12

attract on another

Question 13

electric force and magnetic force are the only forces that can both ___ and ____

Answer 13

attract, repel

Question 14

electromagnetic force

Answer 14

associated with change particles

Question 15

a closed system

Answer 15

the loss of momentum of one object equals the gain in momentum of another momentum is conserved

Question 16

how is momentum measure

Answer 16

units of kilogram- meters per second

Question 17

momentum forumula

Answer 17

momentum = mass x velocity

Question 18

momentum depends on

Answer 18

mas and velocity

Question 19

momentum

Answer 19

the producr of an objects mass and velocity

Question 20

when equal and opposite forces act is it

Answer 20

0

Question 21

action and reaction forces are equal in __ and opposite in ___

Answer 21

size, force

Question 22

what are the two forces in newtons law

Answer 22

action and reaction forces

Question 23

what is newtons third law

Answer 23

whenever one motions ecerts force on a second object, the second object exerts an equal and opposite force

Question 24

forces ____ exist and paris

Answer 24

always

Question 25

a force ___ can exist alone

Answer 25

cannot

Question 26

weight is a measure of the force of ___ acting on an object

Answer 26

gravity

Question 27

mass is a measure of the ____ of an object

Answer 27

inertia

Question 28

doubling the mass of an object also doubles the

Answer 28

weight

Question 29

what unit is mass in

Answer 29

kilograms

Question 30

accerlation and gravity are

Answer 30

meter per second

Question 31

force and weight are in

Answer 31

newtons

Question 32

weight formula :

Answer 32

mass x acceleration

Question 33

weight

Answer 33

the force of gravity acting upon an object

Question 34

newtons second law

Answer 34

accelration _ netforce / mass or a=f/m

Question 35

mass

Answer 35

the measure of the interia of an object

Question 36

the accerleration of an object depends on its

Answer 36

masss

Question 37

unbalanced forces cause objects to change

Answer 37

velocity

Question 38

intertia

Answer 38

the tendancy of an objects reists to change in its motionn

Question 39

newtons first law can be called

Answer 39

intertia

Question 40

the state of motion does not change as long as the netforce acting on the object is

Answer 40

0

Question 41

newton

Answer 41

summerized his study of force and motion in several laws of motion

Question 42

air resisrance and gravity are the only forces acting on

Answer 42

projectile

Question 43

projectile motion

Answer 43

a curved path, the motion of a falling object

Question 44

terminal velocity

Answer 44

the constant velocity of a falling object when the force of air resistance

Question 45

as an object falls to the ground for a long time the ___ force of air resistance becomes __ to the downward force of ___

Answer 45

upward, equal

Question 46

as objects fall to the ground they ___ and ___ speed

Answer 46

accerlate, gain

Question 47

air resistance acts in the direcrion ___ to the motion and ___ acceleration

Answer 47

opposite, reduces

Question 48

what 2 things can affect the motion of falling object

Answer 48

gravity and air resistance

Question 49

earths gravity acts ___ toward the center of the earth

Answer 49

downaward

Question 50

gravity can act over ___ disatnce

Answer 50

large

Question 51

gravity can act over ____ distances

Answer 51

large

Question 52

gravity

Answer 52

a force that acts between any two masses

Question 53

air resistance

Answer 53

fluid friction acting on an object moving through the air

Question 54

fluid friction

Answer 54

opposes the motion of an object through a fluid

Question 55

rolling friction

Answer 55

the friction force that acts on a rolling ojbect

Question 56

because sliding friction is less than startic friction,

Answer 56

less force is needed

Question 57

sliding friction

Answer 57

a force that opposed the direction of motion an object as it slides over a surfaces

Question 58

static friction always acts in the direction ___ to that applied force

Answer 58

opposite

Question 59

static friction

Answer 59

the friction force that acts on objects that are not moving

Question 60

what are the four main types of friction

Answer 60

static, sliding, rolling, fluid

Question 61

friction acts at the surface where objects are in

Answer 61

contact

Question 62

friction

Answer 62

a force that opposes the motion of objects that touch as they move pass each other

Question 63

all moving forces are subject to

Answer 63

friction

Question 64

forces acting in opposite direction can also combine to produce

Answer 64

an unbalanced force

Question 65

what happens when an unbalnced force acts on an object

Answer 65

the object acclerates

Question 66

there are no changes in the objects motion when the net force is

Answer 66

0

Question 67

blanced forces are combined to produce a net force of

Answer 67

0

Question 68

net force

Answer 68

the overall force after all the forces combined

Question 69

can forces be combined

Answer 69

yes

Question 70

what can you use to represent the direction and strength of a force

Answer 70

an arrow

Question 71

who is sir issac newton

Answer 71

newton is named after him, english scientist who explained how force, mass, and acceeration are related

Question 72

1 newton is equal to

Answer 72

1 kilogram-meter per second squared

Question 73

one newton

Answer 73

the force that causes a 1- kilogram mass to accerates at a rate of 1 meter per second each second

Question 74

force is measured in

Answer 74

newton

Question 75

forces are often ___ to measure

Answer 75

easy

Question 76

forces can causse a resting object to move, or it can a ___ moving, object by changing the objects ___ or ___

Answer 76

accelerate, speed, or direction

Question 77

force

Answer 77

a push or pull that acts on an object