Question

A body is weighed by a spring balance to be 1 kg at the north pole . How much will it weigh at the equator ? Account for the earth rotation only

Answer 1

Sol. Let g’ be the acceleration due to gravity at equation & that of pole = g
g’ = g ω^2 R
= 9.81 – (7.3 * 10^-5)^2 * 6400 * 10^3
= 9.81 – 0.034
= 9.776 m/s^2
Mg’ = 1 kg * 9.776 m/s^2
= 9.776 N or 0.997 kg
The body will weight 0.997 kg at equator