Question

An object at the surface of Earth (at a distance R from the center of Earth) weighs 90 N. Its weight at a distance 3R from the center of Earth is:

Answer 1

The weight of an object at a distance 3R from the center of the Earth is calculated using the formula:

w = mg

where w is the weight of the object, m is the mass of the object, and g is the acceleration due to gravity.

The acceleration due to gravity is inversely proportional to the square of the distance from the center of the Earth. Therefore, the acceleration due to gravity at a distance 3R from the center of the Earth is:

g' = g (R/3R)^2 = g/9

where g is the acceleration due to gravity at the surface of the Earth.

The weight of the object at a distance 3R from the center of the Earth is:

w' = mg' = m(g/9) = (1/9)w

Therefore, the weight of the object at a distance 3R from the center of the Earth is 10 N.