The radius of a planet is 2400 km, and the acceleration due to gravity at its surface is 3.6 m/s2. What is the mass of the planet?

Explanation:

We can use Newton's Universal Law of Gravitation to solve this problem:

., where is acceleration due to gravity at the planet's surface, is gravitational constant , is the mass of the planet, and is the radius of the planet.

Since acceleration due to gravity is given as , our radius should be meters. Therefore, convert kilometers to meters:

.

Now plugging in our values, we get:

,

Solving for :

.

f=ma newton's second law 7x8=56n