Circular motion (Unit 3)

Question 1

Radians > Degrees?

Answer 1

x 360/2pi

Question 2

Degrees> Radians?

Answer 2

x 2pi/360

Question 3

How do we use circular motion to make cars safe around curves?

Answer 3

• Appropriate tyre design for friction
• Banking of road

Question 4

What is period?

Answer 4

-time taken for one complete circuit

Question 5

What is Frequency?

Answer 5

-the number of cycles per second

Question 6

What is a radian?

Answer 6

-A unit of measurement of angles equal to about 57.3°

Question 7

What is angular velocity?

Answer 7

• the angle θ swept out by the radius in
  time

Question 8

Angular velocity units?

Answer 8

rad s^-1

Question 9

How is an object moving at constant speed but accelerating?

Answer 9

• its velocity must be changing, as velocity is a vector and the direction is constantly changing
  -As the rate of change of velocity is equal to acceleration, the particle must be constantly accelerating

Question 10

Where is centripetal force and acceleration directed at?

Answer 10

-towards the centre of the circle

Question 11

What is centripetal force?

Answer 11

-the resultant force acting on a body moving at
constant speed in a circle