Question

The escape velocity of a body from earth is about 11.2 km/s. Assuming the mass and radius of the earth to be about 81 and 4 times the mass and radius of the moon, the escape velocity in km/s from the surface of the moon will be:

• A. 0.54
• B. 2.48
• C. 11
• D. 49.5

Answer 1

Answer: (B)

2.48

Formula for escape velocity $=\sqrt{\frac{2GM}{R}}$

Mass of moon $=M$

radius of moon $=r$

Escape velocity $=\frac{2}{9}$ times of earth $=\frac{2}{9}\times 11.2=2.48m/sec$.