Simple Harmonic Motion - Multiple Choice Questions

Q7. A simple pendulum and a mass-spring system both have the same time period T at the surface of the Earth. If taken to another planet where the acceleration due to gravity was half that on Earth, which line, A-D, in the table gives correctly the new periods?

 
simple pendulum
mass-spring
A
T
B
T
C
D

For the pendulum g is inversely proportional to T2.

Therefore if g halved the period would increase (by a factor of root 2).

The spring system's period does not depend on g. It depends on the mass (which is the same wherever the body is) and the spring constant. The spring constant depends on the internal arrangment of the spring's particles. That is unaltered by position in a graviational field.