Time management is very much important in IIT JAM. The eduncle test series for IIT JAM Mathematical Statistics helped me a lot in this portion. I am very thankful to the test series I bought from eduncle.
Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Isha lohan 1
This is the relation where beta is volume expansivity and kappa is isothermal compressibility. This relation is derived from the specific heat equations. If you need derivation I can send you, but you should also learn this formula for being fast in exam as it will save time. Ask if any doubts.