A small part of Nickel tube is fulfilled with mercury.
(Alpha) Linear coefficient of expansion (Nickel)= 1x10^-5
(Beta) Volumetric coefficient of expansion (Mercury)= 18X10^-5
FIND: What part of tube should be fullfilled, that the period of the pendulum would not depend upon temperature. And there is two different cases:
a) When centre of mass coincide with centre of Mercury in that tube.
b) Include misalignment of centres...
Should be more but don't know. Maybe someone could help :-)