(a(i))[1]
State the meaning of balanced forces.
(a(ii))[1]
The frictional force in Fig. 2.1 does not cause any heating effect. State what must occur for the frictional force to produce heating.
(a(iii))[1]
Other than being stationary, describe one further possible state of motion of the box when the forces are balanced.
(b)[3]
If $P = 100\,\text{N}$ and $F = 85\,\text{N}$, the box accelerates. The mass of the box is $25\,\text{kg}$. Calculate the acceleration of the box.