BRAINLIEST WILL BE MARKED FOR THE FIRST ANSWER A body weighs 800 N on earth. Find its weight on a planet whose mass is half of
earth’s mass and radius is twice as earth’s radius. (Take g of earth as 10 m/s2
)

98.4 N

Explanation:

Given that the body weighs 800 N on earth.

Thus,

Weight = mass x acceleration due gravity

i.e W = mg

800 = m x 10

m =

   = 80 kg

The mass of the body is 80 kg.

To be able to determine its weight on the planet, we have to first calculate the gravitational pull of the planet.

But,

g =

Where: G is the Newton's universal gravitation, M is the mass of the planet and r is the radius of the planet.

g =

  =

  = 1.2275

g = 1.23 m/

Thus,

Weight of the body on the planet = mg

                          = 80 x 1.23

                          = 98.4 N

The weight of the body on the planet is 98.4 N