Question

A person has mass 30 kg on the surface of the earth. What is his/her weight on the surface of a planet half massive as earth but with the same size

Answer 1

15 Kg this is the answer

Answer 2

Answer by Kvnmurty

mass m = 30 kg  on Earth

weight = m g = m G M / R²

         G = universal gravitational constant

         M = mass of Earth

         R = Radius of Earth

mass of the body remains same on the surface of other planets.

gravity on a planet = g' = G M' / R' ²

                        M' = M/9        and  R' = R/2

    =>  g ' = G M/R * 4/9 = 4 g / 9

 

weight on the planet = m g' = 4/9 m g  = 4/9 * 30 kg = 40/3  kg