JEE Main · 2025 · 23 Jan 2025 · Shift 2 · EM Waves

A time varying potential difference is applied between the plates of a parallel plate capacitor of capacitance

2.5 μ F

. The dielectric constant of the medium between the capacitor plates is 1 . It produces an instantaneous displacement current of 0.25 mA in the intervening space between the capacitor plates, the magnitude of the rate of change of the potential difference will be

____

Vs^{- 1}

Answer: 100

Solution

The displacement current in a capacitor is

I_{d} = C \frac{d V}{d t}

\frac{d V}{d t} = \frac{I _{d}}{C} = \frac{0.25 \times 1 0 ^{- 3}}{2.5 \times 1 0 ^{- 6}} = 100 V/s

The magnitude of the rate of change of the potential difference is

100 V s^{- 1}

JEE Main · 2025 · 23 Jan 2025 · Shift 2 · Integer answer

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