(a)[1]
State what the term work done means.
(b)[2]
A trolley with mass $400\,\text{g}$ is travelling at a steady speed of $2.5\,\text{m s}^{-1}$ to the right, as shown in Fig. 3.1. Show that the trolley's kinetic energy is $1.3\,\text{J}$.
(c)
The trolley in (b) travels to point P, as shown in Fig. 3.2. At point P, the trolley's speed is $2.5\,\text{m s}^{-1}$. A variable force $F$ acts to the left on the trolley while it moves from P to Q. The way in which $F$ varies with displacement $x$ from P is shown in Fig. 3.3. The trolley is brought to rest at point Q.
(c(i))[3]
Calculate the distance $PQ$.
(c(ii))[2]
On Fig. 3.4, sketch how velocity $v$ varies with $x$ for the trolley moving from P to Q.