The magnetic flux linked to a circular coil of radius R is
$$\phi = 2{t^3} + 4{t^2} + 2t + 5$$ Wb
The magnitude of induced emf in the coil at t = 5 s is
Three vessels of equal capacity have gases at the same temperature and pressure. The first vessel contains helium (monoatomic), the second contains fluorine (diatomic) and the third contains sulfur hexafluoride (polyatomic). The correct statement, among the following is :
An organ pipe filled with a gas at 27$$^\circ$$C resonates at 400 Hz in its fundamental mode. If it is filled with the same gas at 90$$^\circ$$C, the resonance frequency at the same mode will be
The collector current in a common base amplifier using n-p-n transistor is 24 mA. If 80% of the electrons released by the emitter is accepted by the collector, then the base current is numerically :