(a(i))[2]
State the meaning of a field of force.
(a(ii))[2]
State one similarity and one difference between the electric field produced by a point charge and the gravitational field produced by a point mass.
(b)
An isolated solid metal sphere of radius $0.15\,\text{m}$ is placed in a vacuum, as shown in Fig. 5.1. The electric field strength at the sphere’s surface is $84\,\text{V m}^{-1}$. Find:
(b(i))[2]
the charge $Q$ carried by the sphere.
(b(ii))[2]
the electric field strength at point $P$, which is at a distance $x = 0.45\,\text{m}$ from the sphere’s centre.
(c)[3]
Use the information from (b) to plot, on the axes of Fig. 5.2, how the electric field strength $E$ varies with distance $x$ from the centre of the sphere for values of $x$ from $x = 0$ to $x = 0.45\,\text{m}$.