Question

(b) The force, F, between two objects is inversely proportional to the square of the distance, d, between

them.
The distance between two objects is increased by 20%.
Calculate the percentage reduction in the force between the objects.

Answer 1

F is reduced by 31%

Explanation:

F = 1/(d²)

now, we increase the distance by 20% (multiply by 1.2).

F new = 1/(1.2×d)² = 1/(1.44×d²) = (1/1.44) × (1/(d²)) =

= 1/1.44 × old F = 0.69 × old F

100 - 69 = 31%