Physics 2: momentum, energy rotational motion

Question 1

inertia in motion. The product of the mass of an object and its velocity.

Answer 1

momentum

Question 2

Momentum =

Answer 2

mass x velocity OR if direction is not a factor, mass x speed

Question 3

If the momentum of an object changes then either the ___ or the ____ or both change.

Answer 3

mass or velocity

Question 4

also changes momentum

Answer 4

how long a time the force acts

Question 5

both _____ and __ ____ are important in changing momentum

Answer 5

force and time interval

Question 6

impulse =

Answer 6

impulse = the quantity of force x time interval
(Impulse = Ft)

Question 7

change in momentum

Answer 7

impulse

Question 8

When an object ____ the impulses are greater than when the object comes to a stop

Answer 8

bounces

Question 9

only an impulse ____ to a system can change the momentum of the system

Answer 9

external

Question 10

Momentum has both:

Answer 10

direction and magnitude

Question 11

In the absence of an external force, the momentum of a system remains unchanged

Answer 11

Law of Conservation of Momentum

Question 12

colliding objects rebound without lasting deformation or generation of heat

Answer 12

Elastic collision

Question 13

when objects become entangled during the collision; characterized by deformation, or generation of heat, or both.

Answer 13

Inelastic collision

Question 14

Net momentum ____ ____ in any collision regardless of the angle between the paths of the colliding objects

Answer 14

remains unchanged

Question 15

force x distance

Answer 15

Work

Question 16

the unit of measurement of work

Answer 16

joule

Question 17

amount of work done per time it takes to do it.

Answer 17

Power = work done/time interval

Question 18

The unit of power

Answer 18

watt (joules per second)

Question 19

something that enables an object to do work

Answer 19

Energy

Question 20

Energy is measured in ____.

Answer 20

joules

Question 21

2 common forms of mechanical energy:

Answer 21

1. energy due to the position of something

2. the movement of something

Question 22

energy stored and held in readiness

Answer 22

potential energy

Question 23

potential energy due to elevated positions

Answer 23

gravitational potential energy

Question 24

potential energy can change into ____ ____.

Answer 24

kinetic energy

Question 25

energy of motion

Answer 25

kinetic energy

Question 26

1/2 mass x speed x speed =

Answer 26

kinetic energy

Question 27

net force x distance =

Answer 27

kinetic energy

Question 28

work = change in ____

Answer 28

kinetic energy

Question 29

Energy cannot be created or destroyed; it may be transformed from on form into another, but the total amount of energy never changes

Answer 29

Law of Conservation of Energy

Question 30

device for multiplying forces or changing the direction of forces. They work on the principle of conservation of energy

Answer 30

machine

Question 31

one of the simplest machines

Answer 31

lever

Question 32

if the little work done by friction is small enough to neglect, then the work input will equal work output

Answer 32

(Fd)input = (Fd)output

Question 33

point of support on which the lever rotates

Answer 33

fulcrum

Question 34

when the fulcrum is close to a load,

Answer 34

a small input force will produce a large output force

Question 35

useful energy output/total energy input

Answer 35

efficiency

Question 36

linear speed of something moving along a circular path

Answer 36

tangential speed

Question 37

____ ____ is directly proportional to the distance from the axis for any given rotational speed

Answer 37

tangential sped

Question 38

units of tangential speed

Answer 38

m/s or km/h

Question 39

Rotational rates

Answer 39

RPM revolutions per minute

Question 40

When tangential speed undergoes a change

Answer 40

tangential acceleration

Question 41

the property of an object to resist changes in its rotational state of motion

Answer 41

rotational inertia

Question 42

rotational inertia depends on ____ about axis of rotation

Answer 42

mass

Question 43

the rotational counterpart of force

Answer 43

torque

Question 44

if you want to make a stationary object rotate apply ___

Answer 44

torque

Question 45

lever arm x force =

Answer 45

torque

Question 46

the average position of all the mass that makes up the object

Answer 46

center of mass

Question 47

used to express center of mass. It is the average position of weight distribution

Answer 47

center of gravity

Question 48

ideal way to increase stability

Answer 48

wide BOS and lower COG

Question 49

rotational inertia x rotational velocity

Answer 49

Angular momentum