Circular motion and Oscillations

Question 1

Define Centripetal acceleration

Answer 1

Acceleration of any object travelling in a circular path at constant speed, always acts towards the centre of a circle

Question 2

Define SHM

Answer 2

Oscillation motion for which a is directly proportional to x and is directed towards some fixed point- characterised by a=-(w^2)X

Question 3

Define damping

Answer 3

Oscillations in which the kinetic energy is converted into other forms i.e. heat and so the amplitude of the
oscillation reduces.

Question 4

Define free oscillations

Answer 4

When an object oscillates without a driving force acting to keep it oscillating. Objects undergoing free
oscillations vibrate at their natural frequency

Question 5

Define Natural frequency

Answer 5

The frequency of the free oscillations of a system

Question 6

Define forced oscillations

Answer 6

Oscillation in which a periodic driver force is applied to an oscillator

Question 7

Driving Frequency

Answer 7

Frequency with which a periodic driver is applied to a system in forced oscillation

Question 8

Define Resonance

Answer 8

When the driving frequency is equal to the natural frequency of an oscillating system. This causes a
dramatic increase in the amplitude of the oscillations.

Question 9

How would you find F & V from whirling bung experiment? 5 marks

Answer 9

• Student tries to rotate bung at a constant radius
• Force F is calculated from F=mg, where m is mass of the slotted masses
• Measure time t for n revolutions of the bung
• Measure radius r when stationary
• Calculate v using 2PiR/t.

Question 10

When would you use X=ACosWT?

Answer 10

When pendulum released from highest point and oscillations timed from that point.

Question 11

Define Displacement

Answer 11

Distance (of the body) from equilibrium position.