Obtain the expression for the energy density of magnitude field B produced in the inductor.
Show that the current leads the voltage in phase by in an ac circuit containing an ideal capacitor.
In an A.C. circuit, Irms and I₀ are related as
(a) Irms = p I₀
(b) Irms = 2 I₀
(c) Irms = I₀/p
(d) Irms =I₀ / 2
In electric arc furnace Cu or Iron is melted due to variation of
(a) current
(b) magnetic field
(c) voltage
(d) electric field
State which of the two a capacitor or an inductor, tends to become SHORT when the frequency of the applied alternating voltage has a high value.
A device ‘X’ is connected to an ac source V = V₀ sin(ωt). The variation of voltage, current and power in one complete cycle is shown in the following figure.
(i) Which curve shows power consumption over a full cycle?
(ii) Identify the device ‘X’.
Why do the electric field lines never cross each other ?
The emf of a cell is always greater than its terminal voltage. Why ? Give reason.
How does the random motion of free electrons in a conductor get affected when a potential difference is applied across its ends ?
For any charge configuration, equipotential surface through a point is normal to the electric field. Justify.
When electrons drift in a metal from lower to higher potential, does it mean that all the free electrons of the metal are moving in the same direction ?