3.6.1.1 - Circular Motion

Question 1

When does uniform circular motion occur?

Answer 1

When an object rotates at a constant or steady rate.

Question 2

Radians -> degrees?

Answer 2

180/π x rad angle

Question 3

Degrees -> radians?

Answer 3

π/180 x degrees

Question 4

Linear speed =

Answer 4

2 πr / T

Question 5

What is angular speed?

Answer 5

The angular displacement per second.

Question 6

What is the unit for angular displacement?

Answer 6

rads-1

Question 7

What is the angle in angular speed always measured in?

Answer 7

Radians

Question 8

Describe the velocity in centripetal acceleration?

Answer 8

Velocity is at a tangent to the circle.

Question 9

Why is there acceleration in a circle?

Answer 9

Because the velocity is always changing direction and as it is a vector there is acceleration.

Question 10

Where are centripetal force and acceleration both directed towards?

Answer 10

The centre of the circle.

Question 11

Is there any work done on the object due to centripetal force?

Answer 11

No because the object is moving in a circular path/

Question 12

What is the centripetal force?

Answer 12

The resultant inward force towards the centre of the circle.

Question 13

If an object is on a hill what is the centripetal force?

Answer 13

Mg - s

Question 14

If an object is at the bottom of a circle, like the Big Dipper, what is the centripetal force?

Answer 14

S - mg

Question 15

If a person is at the top of a Ferris wheel what is the centripetal force?

Answer 15

S + mg

Question 16

What happens when s = 0?

Answer 16

There is no contact with the ground.

Question 17

If something is on a curved track what is the horizontal component and what is it equal to?

Answer 17

R sin 0 = mv^2 / r

Question 18

If something is on a curved track what is the vertical component and what is it equal to?

Answer 18

R cos 0 = mg