Question

The intensity of gravitational field at a point situated at a distance 8000 km from the centre of earth is 6.0 newton /kg. The gravitational potential at that point in newton - meter/kg will be:

• A. 6
• B. $4.8\times {10}^7$
• C. $8\times {10}^5$
• D. $4.8\times {10}^2$

Answer 1

The correct option is B $4.8\times {10}^7$

Gravitational field and potential at a distance r are $E$ and $V$ respectively.

$E=\frac{GM}{r^2}V=\frac{GM}{r}$

Thus $V=Er=6\times 8\times {10}^6$

$V=4.8\times {10}^{7}Nm/kg$