Question

The mass of a body is 40 kg find the weight of the body on the surface of planet whose mass is doubled and the mass of the earth and radius is 4 times the radius of the earth

Answer 1

See the above image...

Answer 2

Hello friend,

◆ Answer-

W = 49 N

◆ Explaination-

Let M & M' be mass of earth & given planet. Also R & R' be their radius respectively.

Given is -

M' = 2M

R' = 4R

Gravitational accelaration on earth surface is -

g = GM / R^2

Gravitational accelaration on supposed planet is -

g' = GM' / R'^2

g' = G(2M) / (4R)^2

g' = GM / 8R^2

g' = g / 8

g' = 9.8 / 8

g' = 1.225 m/s^2

Weight of the body on planet is -

W = mg'

W = 40 × 1.225

W = 49 N

Therefore, weight of the body on given planet is 49 N.

Hope this helps...