Chapter 16 - Circular motion

Question 1

convert radians to degrees

Answer 1

multiply by 360/2π

Question 2

convert degrees to radians

Answer 2

multiply bu 2π/360

Question 3

define Period

Answer 3

time, in seconds, for an object to travel a full circle

Question 4

define frequency

Answer 4

number of completed circles per second

Question 5

equation for time period

Answer 5

1/f

Question 6

Define angular velocity, ω

Answer 6

rate of change of angle

Question 7

Equation for angular speed regarding an angle and time

Answer 7

ω = θ/t where θ is the angle the object has sweeped out in radians

Question 8

general equations for angular velocity

Answer 8

2π/T so 2πf

Question 9

What happens to direction during circular motion and therefore velocity

Answer 9

direction constantly changes so velocity constantly changes even though speed is constant

Question 10

If the velocity is changing constantly due to directional change in circular motion, what does there need to be.

Answer 10

An acceleration and therefore a force, this force is called the centripetal force.

Question 11

Define centripetal force

Answer 11

Net force that acts perpendicular to the direction of the velocity, towards the centre of the circle.

Question 12

Derive equation for centripetal force

Answer 12

v = 2πr/t = ωr
a = v^2/r = ω^2r
F = mv^2/r = mω^2r