6. Motion in a Circle

Question 1

What is angular displacement?

Answer 1

Angular displacement is the angle through which an object turns, usually measured in radian.

Question 2

What is the formula of angular displacement?

Answer 2

𝛉 = s/r
s= arc length
r = radius of circle

Question 3

What is angular velocity?

Answer 3

angular velocity is defined as the rate of change of angular displacement.

Question 4

What is the formula of angular velocity w?

Answer 4

w = d𝛉/dt

Question 5

What is the formula relating Angular velocity w and Linear velocity v ?

Answer 5

v = r w

Question 6

For an object going through uniform circular motion, what is the equation for angular velocity?

Answer 6

w = Δ𝛉/Δt
= 2∏ / T , 2∏f

Question 7

What is the formula of centripetal acceleration?

Answer 7

a = rw² = v w = v²/r

Question 8

What is the formula of centripetal force?

Answer 8

F net = m r w² = m v w = m v² / r

Question 9

In non-uniform circular motion, how to calculate maximum/minimum speed such that object remains in contact?

Answer 9

equate W - N = mv² / r ( outside circle) W + N = mv² / r , make N the subject, sub W = mg
since stay in contact, N≥0
v = √rg

Question 10

What is radian?

Answer 10

One radian refers to the angle subtended at the centre of a circle by an arc equal in length to its radius.