Momentum Questions

Q5. The simplified diagram shows an experimental arrangement to investigate the collision of two trolleys.

In the experiment, trolley A is travelling at speed ν. It collides with and sticks to, the initially stationary trolley B.

(a) State the measurements you would need to take so that you could determine the speed of

(i) trolley A before the collision,

length of card [or distance travelled by trolley A ]

time at which first light gate is obscured [or time taken to travel the distance ]

(ii) trolleys A and B after the collision.

time at which second light gate is obscured [or distance travelled after collision and time taken ]

(3 marks)

(b) Explain how you would verify that momentum was conserved in this collision, indicating what other measurements would be required.

Momentum = mass × velocity therefore I would need to find the mass of each trolley. I would then need to calculate the initial and final momentum totals to (check whether pinitial = pfinal

(2 marks max)

(c) State and explain what you would do to minimise the effects of friction on the motion of the trolleys.

You could incline the ramps until the component of weight balances friction

[OR identify where the friction occurs and oil the moving parts to reduce friction]

(2 marks)

(7 Marks Total)