Question

weight of 2 bodies are 20N and 30N. if they are separated by a distance of 2m, what is the force of gravitation acting between them?

Answer 1

Given: Weight of first body (w₁) = 20 N

Weight of second body (w₂) = 30 N

The separation between these two bodies (r) = 2 m

Let g = 9.8 m/s² be the gravitational acceleration.

Mass of first body (m₁) = (20 / g) kg

Mass of first body (m₂) = (30 / g) kg

The universal gravitational constant 'G' = 6.67 ×10⁻ ¹¹ N m² kg⁻²

Concept: Newton's Law of Gravitation Attraction,

The force of gravitation attraction (F) is given as

$F = G \frac{m_{1} . m_{2}}{r^{2}}$

or, F = (6.67 ×10⁻ ¹¹ N m² kg⁻²)× (20 /g) kg ×(30 /g) kg / (2 m)²

or, F = 10.4 ×10⁻ ¹¹ N

Hence, the required force will be 10.4 ×10⁻ ¹¹ N.