Question

Weight of the on the object on the earth is 300N. What is the weight of the object on the planet whose mass is 3times to the mass of the earth and radius of the planet is 4times to the radius of the earth.

Answer 1

The gravitational acceleration on earth's surface is g=

R

2

GM

​

For planet, M

p

​

=M/7 and R

p

​

=R/2

So, g

p

​

=

R

p

2

​

GM

p

​

​

=

(R/2)

2

G(M/7)

​

=

7

4

​

g

Thus, weight of the body on planet's surface =300g

p

​

=300(4/7)=400