Physics 9702 · AS & A Level · Damped and forced oscillations, resonance

Damped and forced oscillations, resonance — practice question

(a)[2]

State, with reference to displacement, the meaning of simple harmonic motion.

(b)[2]

A mass is oscillating in a vertical plane. Fig. 3.1 shows how the acceleration $a$ of the mass varies with displacement $x$. State two reasons why the motion of the mass is not simple harmonic.

(c(i))[2]

A block of wood is floating in a liquid, as shown in Fig. 3.2. The block is moved vertically and then let go. Fig. 3.3 shows how the displacement $y$ of the block from its equilibrium position varies with time $t$. Use the information in Fig. 3.3 to find the angular frequency $\omega$ of the oscillations.

(c(ii))[2]

Use the data in Fig. 3.3 to determine the maximum vertical acceleration of the block.

(c(iii))[3]

The block has mass $120\,\text{g}$. Its oscillations are damped. Calculate the loss in energy of the block's oscillations over the first three complete periods.

Worked solution & mark scheme

This 11-mark question has a full step-by-step worked solution and mark scheme. One marking point: Acceleration/force proportional to displacement from fixed point

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI