Point X is at a distance from the centre of Earth

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

Point X is at a distance

d

from the centre of Earth.

d

is larger than the radius of Earth. The gravitational field strength at X is

g_x

. Point Y is at a distance

3d

from the centre of Earth. What is the difference in the magnitude of gravitational field strengths between X and Y? (A)

\frac{8g_x}{9}

(B)

\frac{3g_x}{4}

(C)

\frac{g_x}{4}

(D)

\frac{g_x}{9}