Q73 of 176 Page 103

Suppose a planet exists whose mass and radius both are half those of the earth. Calculate the acceleration due to gravity on the surface of this planet.

Acceleration due to gravity of earth,

g = G * M/ R2 = 9.8 m/s2


If mass of planet, m =


And radius of planet, r =


Acceleration due to gravity on the surface of the planet will be:


g = G * m / r2 (i)


m = (ii)


r = (iii)


Put (ii) and (i) in equation (i), we get


g = * (G * M / R2)


g = 2 * 9.8 m/s2


g = 19.6 m/s2


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