Question

A capacitor is charging in a simple RC circuit with a dc battery. Which one of the following statements about this capacitor is accurate?Answera)There is a magnetic field between the capacitor plates, even though no charge travels between them, because the magnetic flux between the plates is changing.b)The magnetic field between the capacitor plates is increasing with time because the charge on the plates is increasing.c)There is no magnetic field between the capacitor plates because no charge travels between the plates.d)There is a magnetic field between the capacitor plates because charge travels between the plates by jumping from one plate to the other.e)There is a magnetic field between the capacitor plates, even though no charge travels between them, because the electric flux between the plates is changing

Answer 1

Answer:

Option e

Explanation:

In the case of simple RC circuit, connected with a DC source, the charging of the capacitor after the switch is closed and the current starts to flow resulting in the accumulation of charge on the capacitor plate.

The capacitor is charged to the point where the voltage across the capacitor becomes equal to the emf of the battery and at this point no current flows and the capacitor has stored maximum charge.

No current flows when the voltage equals the emf and there is no voltage drop in the resistance of the circuit, but as the capacitor is charged, there exist an electric field and the variation of the voltage in the charging over the time is given by:

$V = E(1 - e^{-\frac{t}{RC}})$

where

V = voltage

E = emf of the battery

t = time

R = Resistance

C = Capacitor

The variation of the current is given by:

$I = \frac{E}{R}$

Thus there exist a magnetic field between the plates of the capacitor, even when there flows no charge  as the current and hence the electric flux between the plates changes.