Which of the following graphs between pressure (P) and volume (V) correctly shows isochoric changes?

A metal rod $$2 \mathrm{~m}$$ long increases in length by $$1.6 \mathrm{~mm}$$, when heated from $$0^{\circ} \mathrm{C}$$ to $$60^{\circ} \mathrm{C}$$. The coefficient of linear expansion of metal rod is

We have a jar filled with gas characterized by parameters $$\mathrm{P}, \mathrm{V}, \mathrm{T}$$ and another jar B filled with gas having parameters $$2 \mathrm{P}, \frac{\mathrm{V}}{4}, 2 \mathrm{~T}$$, where symbols have their usual meaning. The ratio of number of molecules in jar A to those in jar B is

An insulated container contains a monoatomic gas of molar mass '$$\mathrm{m}$$'. The container is moving with velocity '$$\mathrm{V}$$'. If it is stopped suddenly, the change in temperature of a gas is [R is gas constant]