IB Questionbank

User interface language: English | Español

Question

The graph below represents the variation with time t of the horizontal displacement x of a mass attached to a vertical spring.

M18/4/PHYSI/HP3/ENG/TZ1/11

The total mass for the oscillating system is 30 kg. For this system

Describe the motion of the spring-mass system.

[1]

determine the initial energy.

[1]

b.i.

calculate the Q at the start of the motion.

[2]

b.ii.

damped oscillation / OWTTE

[1 mark]

E «= $\frac{1}{2}$ × 30 × π² × 0.8²» = 95 «J»

Allow initial amplitude between 0.77 to 0.80, giving range between: 88 to 95 J.

[1 mark]

b.i.

ΔE = 95 – $\frac{1}{2}$ × 30 × π² × 0.72² = 18 «J»

Q = « 2π $\frac{{95}}{{18}}$ =» 33

Accept values between 0.70 and 0.73, giving a range of ΔE between 22 and 9, giving Q between 27 and 61.

Watch for ECF from (b)(i).

[2 marks]

b.ii.

[N/A]

b.i.

[N/A]

b.ii.