Question

$\begin{gathered} \\ \Large{\bf{\pink{\underline{The \: Question \::}}}} \\ \end{gathered}$

A body weighs 700 g wt on the surface of the earth. How much will it weigh on the surface of a planet whose mass is 1/7 and radius is half that of the earth

​

Answer 1

Answer:

It's very simple

Use the formula of gravitational force ok?

Explanation:

Answer 2

Answer:

According to Newton, F = G * m1 * m2 / R^2

Where m1 and m2 are the two masses and R is the distance between them.

You can certainly do a three dimensional integral of the above force to find out the answer, but all you really need to know are the scaling laws that apply.

First, if m2 is the planet, and it has a different mass than Earth, the resulting force will be proportional to the planetary mass. So 1/7 the mass will lead to 1/7 the force.

Second, if the radius is different, the force will be proportional to the square of the the radius. If the radius goes from 1 to 1/2 the force will go from 1 to 4.

Combining the two effects gives 1/7 * 4 = 4/7.

If the original weight was 700g force, the new weight will be 400 g force.