Year 13 - Further Mechanics

Question 1

Angular Displacement

Answer 1

The angle subtended at centre of a circle by an arc of equal length to the radius.

Question 2

Angular Speed

Answer 2

The rate of change of angular displacement with respect to time or the amount of angle in radians swept out in a given time.

Question 3

Centripetal Acceleration

Answer 3

The acceleration of an object moving in circular motion. An object can have a constant speed; but must have an acceleration since the direction of the object/velocity of the object, is constantly changing. The acceleration is perpendicular to the motion.

Question 4

Centripetal Force

Answer 4

The resultant force responsible for an object moving in circular motion. Centripetal forces always act towards the centre of the object’s rotation E.g. Perpendicular to the motion.

Question 5

Critical (Heavy) Damping

Answer 5

The form of damping that reduces the displacement of an oscillating object to its equilibrium position in the quickest time possible and without further oscillation.

Question 6

Damping

Answer 6

Dampingis the process whereby energy is taken from an oscillating system e.g. Air Resistance on a pendulum.

Question 7

Displacement (Oscillations)

Answer 7

The distance of the oscillating particle from its equilibrium/rest position at any instant.

Question 8

Driving Force

Answer 8

The force which is causing the forced vibration. E.g. Barton’s Pendulum.

Question 9

Forced Vibration

Answer 9

Oscillation due to (external) periodic driving force [or oscillation at the frequency of another vibrating system].

Question 10

Free Vibration

Answer 10

System displaced and left to oscillate, there is no driving force.

Question 11

Natural Frequency

Answer 11

Natural frequencyof the system is the frequency at which it will vibrate freely. Also known as the resonant Frequency.

Question 12

Over Damping

Answer 12

A type of damping where the system is damped more than required to stop the oscillations. It takes longer for the system to return to equilibrium than for critical damping.

Question 13

Resonance

Answer 13

Forced vibrations where amplitude (of vibrations/oscillations) is at a maximum. Frequency of forced vibrations equals natural/resonant frequency.

Question 14

Simple Harmonic Motion (SHM)

Answer 14

Acceleration is directly proportional to displacement from rest position and directed in opposite direction, towards rest position.

Question 15

Under (Light) Damping

Answer 15

A type of damping where energy is gradually removed from the system and the amplitude of oscillations slowly decreases.