Unit 5 - Rotation, Energy, Work & Momentum

Question 1

angular displacement

Answer 1

the change in the angle as an object rotates

theta = s/r

Question 2

angular velocity

Answer 2

The angular displacement of an object divided by the time needed to make the displacement.

omega = delta(theta/delta(t)

Question 3

angular acceleration

Answer 3

change in rate of rotation

alpha = delta(omega)/delta(t)

Question 4

moment of inertia

Answer 4

the resistance to rotation

I=Emr^2

Question 5

angular momentum

Answer 5

the quantity of rotation of a body, which is the product of its moment of inertia and its angular velocity.

Question 6

torque

Answer 6

a turning or twisting force

Question 7

collision

Answer 7

A situation in which two objects in close contact exchange energy and momentum

Question 7

elastic collision

Answer 7

one in which there is no net loss of total kinetic energy

Question 8

inelastic collision

Answer 8

a type of collision in which the kinetic energy after the collision is less than the kinetic energy before the collision

Question 9

Momentum

Answer 9

The product of an object’s mass and velocity

p=mv

Question 10

Impulse Momentum Theory

Answer 10

states that the impulse on an object equals the object’s final momentum minus the object’s initial momentum

Fdelta(t)=mdelta(v)
^ Impulse ^Change in momentum

Question 11

Impulse approixmation

Answer 11

reasonably neglecting small forces during the brief time of the impulsive force

Question 12

Internal forces

Answer 12

a force that acts on an object from the inside

Question 13

External forces

Answer 13

forces that act on an object as a result of its interaction with the environment surrounding it

Question 14

Isolated system

Answer 14

A system that can exchange neither energy nor matter with its surroundings.

Question 15

Law of Conservation of Energy

Answer 15

the law that states that energy cannot be created or destroyed but can be changed from one form to another

Question 16

Law of Conservation of Momentum

Answer 16

law stating that the total momentum of a system does not change if no net force acts on the system

Question 17

Kinetic energy

Answer 17

energy of motion

KE=1/2mv^2

Question 18

Potential energy

Answer 18

stored energy

Question 19

Elastic potential energy

Answer 19

the energy of stretched or compressed objects

Question 20

Gravitational potential energy

Answer 20

Potential energy that depends on the height of an object

Question 21

Mechanical energy

Answer 21

Kinetic or potential energy associated with the motion or position of an object

Question 22

conservative force

Answer 22

a force that does the same work for any given initial and final configuration, regardless of the path followed

KEi+PEi+Wnc=KEf+PEf
Wnc= deltaE

Question 23

non-conservative forces

Answer 23

forces that do work in such a manner that thermal energy is involved and mechanical energy is not conserved. examples are friction and fluid resistance along with horizontal pushing or pulling forces

Question 24

work

Answer 24

Fd forcexdistance

Question 25

work-energy theorem

Answer 25

the theorem that states that whenever work is done, energy changes. W = Δ KE

Question 26

Power

Answer 26

the rate at which work is done