A probe is launched from the surface of Earth into a circular orbit above the surface

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

Problem

A probe is launched from the surface of Earth into a circular orbit

1000\,\text{km}

above the surface. An identical launch is made on Mars. Given

G = 6.67\times10^{-11}\,\text{N\,m}^{2}\,\text{kg}^{-2}

, Earth’s mass

5.97\times10^{24}\,\text{kg}

, radius

6.4\times10^{6}\,\text{m}

, Mars’ mass

6.42\times10^{23}\,\text{kg}

, radius

3.4\times10^{6}\,\text{m}

, the ratio

\frac{\text{energy required per kilogram on Earth}}{\text{energy required per kilogram on Mars}}

is approximately (a)

1

(b)

0.5

(c)

5

(d)

3