Question

A person can lift the maximum of $15kg$ on the Earth. If the moon's gravity is $\frac{1}{6}th$ of the Earth, what will be the maximum mass he can lift?

• A. $60kg$
• B. $70kg$
• C. $80kg$
• D. $90kg$

Answer 1

The correct option is D

$90kg$

Acceleration due to gravity on earth is $g$. So, acceleration due to gravity on moon will be $\frac{g}{6}$.
Force applied to lift a mass of $15kg$ on the earth, $F=mg=15gN$
Force applied to lift a mass of $15kg$ on the moon, $F=m\frac{g}{6}N$
Therefore, mass which can be lifted by the same force applied by the person on the moon $=m=\frac{F}{\frac{g}{6}}=\frac{15g}{\frac{g}{6}}=15\times 6=90kg$