Rotational motion

Question 1

Equation for velocity involving angular velocity?

Answer 1

V=r x omega

Question 2

Equation for acceleration involving angular acceleration?

Answer 2

a=r x alpha

Question 3

Equation for angular momentum?

Answer 3

L=Ixomega

Question 4

Equation for torque?

Answer 4

tau=I x alpha

Question 5

Equation for rotational kinetic energy?

Answer 5

KE=1/2 x I x omega^2

Question 6

Can we compare linear suvat to rotation?

Answer 6

Yes. S = x, U = omega_0, V = omega, a = alpha, t=t

Question 7

Rotational work?

Answer 7

Integral of tau x dtheta

Question 8

Rotational power?

Answer 8

P = tau x omega

Question 9

When is angular momentum is conserved?

Answer 9

If there is no torque. Occurs when r and F are parallel

Question 10

Another equation for torque involving AM?

Answer 10

tau = dL/dt

Question 11

What happens when a pulley has mass?

Answer 11

The tension (T1-T2) generated a torque and torque needs to be considered in calculation of fricition

Question 12

When does the magnitude of L change?

Answer 12

When torque has a component parallel to L

Question 13

When does the direction of L change?

Answer 13

When torque has a component perpendicular to L

Question 14

Angular momentum when object is translating and rotating?

Answer 14

L = (Rxp) + (Sum of r’ x p’)

Question 15

Kinetic energy when an object is translating and rotating?

Answer 15

KE = 1/2Mv^2+1/2I0omega^2

Question 16

What is the time of 1 revolution when rolling?

Answer 16

T=2pi/omega

Question 17

Linear speed of CM when rolling?

Answer 17

Vcm=r x omega

Question 18

What role does friction play when rolling?

Answer 18

Friction causes torque and needs to be considered in calculations

Question 19

When hitting things, what changes?

Answer 19

Impulse can change both linear and angular momentum

Question 20

What happens when impulse if through CM?

Answer 20

Whole body moves with velocity V and no angular motion

Question 21

When is there no impulse effect?

Answer 21

When h x omega = velocity

Question 22

Condition for pure rolling?

Answer 22

v=rw

Question 23

When rolling down a slope, what is a good method to find certain values?

Answer 23

Use conservation of energy

Question 24

What does friction cause?

Answer 24

A torque