Physics 9702 · AS & A Level · Momentum and Newton's laws of motion
Momentum and Newton's laws of motion — practice question
A truck R of mass $9400\,\text{kg}$ travels down a slope in a straight line with constant acceleration, as shown in Fig. 3.1. At point A the truck has speed $13\,\text{m s}^{-1}$ and at point B its speed is $22\,\text{m s}^{-1}$. The distance from A to B is $180\,\text{m}$.
(a(i))[2]
Calculate the acceleration of the truck from A to B.
(a(ii))[3]
Determine the increase in kinetic energy of the truck from A to B.
(b(i))[1]
Define force.
(b(ii))[1]
Show that the average resultant force $F$ on truck R between time $t = 0$ and $t = 15\,\text{s}$ is $-1.2 \times 10^{4}\,\text{N}$.
(b(iii))[3]
An identical truck S has the same initial momentum as truck R. Truck S experiences a constant force equal to the force $F$ in b(ii). State and explain whether truck S will take more, less or the same amount of time to come to rest as truck R.
Worked solution & mark scheme
This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Apply $a = \frac{v^2 - u^2}{2s}$ or another equivalent kinematics relation” …