CHAPTER 10: OSCILLATIONS

Question 1

conditions for simple harmonic motion

Answer 1

1. acceleration is proportional to the displacement from a fixed point
2. direction of acceleration is always opposite to the displacement

Question 2

features of graph

Answer 2

1. straight line passing through origin (a prop to x)
2. negative gradient (a and x act in opp directn)

Question 3

angular frequency

Answer 3

rate of change of phase of oscillator (constant)

Question 4

free oscillation

Answer 4

object oscillates under a restoring force only, without any other external forces on it
no resistive forces

Question 5

damped oscillation

Answer 5

decreasing amplitude due to resistive forces -> loss of energy

light: amplitude decreases gradually with time -> object oscillating in air/water
critical: body does not oscillate and returns to eqm pos in shortest possible time -> car suspension system
heavy: body will take a long time to return to eqm pos without oscillating -> swing door

Question 6

forced oscillation

Answer 6

oscillator is made to oscillate at the frequency of an external driver

Question 7

resonance

Answer 7

phenomenon where the amplitude of the oscillator reaches a maximum when the driving frequency of the drier is equal to the natural frequency of the oscillator. max amplitude implies that there is maximum transference of energy to the oscillator

Question 8

effects of damping

Answer 8

1. curve is shifted lower
2. flatter peak
3. shifts slightly to the left