If a pendulum has a period of 4 seconds at the north pole with gravity force 9.83 ms^-2 and a 3.97m pendulum length, how could the same pendulum be adjusted to have the same period as the equator with 9.78ms^-2 gravity force?

The same pendulum could be adjusted to have the same period, in the equator must have a length of 3.949m.

Explanation:

Tnp = 4 sec

gnp = 9.83 m/sec²

Lnp = 3.97m

Tequ = 4 sec

gequ = 9.78 m/sec²

Lequ=?

Lequ = (Lnp * gequ) / gnp

Lequ = 3.949 m