## Question

What will be the acceleration due to gravity on the surface of the moon if its radius is 1/4^{th} the radius of the earth and its mass is (1/80)th the mass of the earth.

### Solution

1/5

The acceleration due to gravity on the surface of the earth, in terms of mass *M _{e}* and radius

*R*of earth, is given by

_{e}

If *M _{m}* be the mass of the moon,

*R*its radius, then the acceleration due to gravity on the surface of the moon will be given by

_{m}

Dividing eq. (ii) by eq. (i), we get

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