Phys - Vibrations

Question 1

Simple Harmonic Motion

Answer 1

Periodic motion of a body due to a restoring force which is proportional to its displacement from a fixed equillibrium point and always points in the opporite direction from said displacement.

Question 2

Resonance

Answer 2

Forced oscillation due to a driving force at a fixed frequency, where any object has a specific resonant frequency that achieves maximum amplitude.

Question 3

Damping - Light

Answer 3

Amplitude progressively decreases over time due to a resistive force, but period remains the same

Question 4

Damping - Heavy

Answer 4

An object asymptotically approaches the fixed equillibrium point, due to a resistive force.

Question 5

Damping - Critical

Answer 5

An object takes the smallest amount of time possible to get to 0 (quarter of an oscillation), due to a resistive force

Question 6

Damping

Answer 6

Energy is dissapated from an SHM system, leading to a reduction in amplitude

Question 7

Practical Damping Example

Answer 7

Vehicle suspension systems use critical damping to minimise the oscillation and avoid large amplitudes of the vehicle, returning to a stable equillibrium as quickly as possible.

Question 8

Useful Resonance Example

Answer 8

The microwave oven’s cavity resonates at the frequency of the mixrowaves generated, keeping in energy more efficiently.

Question 9

Not Useful Resonance Example

Answer 9

Bridges experience periodic forces like footsteps or wind, which can match the resonant frequency of the bridge’s material and cause it to oscillate at an unsafe amplitude.