Question

If all objects that have mass also have gravity, why doesn't your pencil get pulled towards you while it sits on your desk?

Answer 1

Answer:

The pencil is not pulled towards a person due to a very small magnitude of force between them, due to lighter masses.

Explanation:

Let us apply Newton's Law of Gravitation between a person and pencil.

Average Mass of a Normal Pencil = m₁ = 10 g = 0.01 kg

Average Mass of a Person = m₂ = 80 kg

Distance between both = r = 1 cm = 0.01 m (Taking minimal distance)

Gravitational Constant = G = 6.67 x 10⁻¹¹ N.m²/kg²

So,

F = Gm₁m₂/r²

F = (6.67 x 10⁻¹¹ N.m²/kg²)(0.01 kg)(80 kg)/(0.01 m)²

F = 5.34 x 10⁻⁷ N

This Force is very small in magnitude due to the light masses of both objects.

Therefore, the pencil is not pulled towards a person due to a very small magnitude of force between them, due to lighter masses.