(a(i))[1]
State what gravitational field strength means.
(a(ii))[1]
Explain why, at a planet’s surface, the numerical value of gravitational field strength matches the acceleration of free fall.
(b)[3]
A spherical planet of uniform density has radius $R$. The acceleration of free fall at its surface is $g$. On Fig. 1.1, sketch a graph to show how the acceleration of free fall varies with distance $x$ from the centre of the planet for $x$ in the range $R$ to $4R$.
(c)[3]
For the planet in (b), $R = 3.4 \times 10^{3}\,\text{km}$ and the mean density is $4.0 \times 10^{3}\,\text{kg m}^{-3}$. Calculate the acceleration of free fall at a height $R$ above its surface.