A nuclide at rest emits an $\alpha$-particle. In this process
If 2 moles of an ideal monoatomic gas at temperature $$T_0$$ is mixed with 4 moles of another ideal monoatomic gas at temperature $$2 T_0$$, then the temperature of the mixture is
The system is pushed by a force $$F$$ as shown in figure. All surfaces are smooth except between $$B$$ and $$C$$. Friction coefficient between $$B$$ and $$C$$ is $$\mu$$. Minimum value of $$F$$ to prevent block $$B$$ from downward slipping is
A parallel plate capacitor with plate area $$A$$ and separation between the plates $$d$$ is charged by a constant current $$i$$. Consider a plane surface of area $$A / 2$$ parallel to the plates and drawn simultaneously between the plates. The displacement current through this area is