6: Circular Motion

Question 1

Define angular displacement

Answer 1

Angular displacement is the angel of rotation of a body about an axis in a specific direction

Question 2

Define angular velocity

Answer 2

Angular velocity is the rate of change of angular displacement

Question 3

Equation for Linear velocity

Answer 3

L.velocity = radius x angular velocity

Question 4

Eqn for angular velocity

Answer 4

angluar velocity = 2 x pi x freq = (2 x pi)/T

Question 5

Define period

Answer 5

Period is the time taken for one complete oscillation

Question 6

Define frequency

Answer 6

Frequency refers to the number of revolutions per unit time

Question 7

Why must object in cm experience force?

Answer 7

1. Moving in circles, thus directions always changing and hence velocity always changing
2. By N1L; there must be external resultant force on object to change direction

Question 8

Why is centripetal force/ acceleration towards center?

Answer 8

1. Velocity always changing but linear speed remains constant
2. Thus force must be perpendicular to speed so that no work is done on the object’s speed

Question 9

Eqn of centripetal acceleration

Answer 9

c.a = v^2/r = r x angular velocity^2= v x angular velocity