3.6.1 Periodic motion

Question 1

Motion in a circular path at a constant speed implies there is an ….. and requires a …….

Answer 1

Motion in a circular path at constant speed implies there is
an acceleration and requires a centripetal force

Question 2

What is the unit for angular speed?

Answer 2

Radians per second (rads^-1)

Question 3

What is the angular speed?

Answer 3

The angle that an object moves through per unit time

Question 4

What is the equation for angular speed? (3)

Answer 4

ω = v/r = 2π/T = 2πf

Question 5

How do Newton’s laws explain the existence of a centripetal force?

Answer 5

We know from Newton’s first law that to accelerate, an object must
experience a resultant force

Question 6

What is a radian?

Answer 6

The angle of a sector when the arc length is equal to the radius

Question 7

How many radians are in a circle?

Answer 7

2π radians

Question 8

What is the equation for centripetal acceleration? (2)

Answer 8

a = v²/r = ω²r

Question 9

What is the centripetal force?

Answer 9

The force that acts on a body moving in a circular path and is directed towards the centre of the circle

Question 10

What is the equation for centripetal force? (2)

Answer 10

F = mv²/r = mω²r