Question

The plates of a parallel plate capacitor are 4 cm apart ,the first Plate is at 300 V and the second plate at -100 V.The voltage at 3 cm from the second plate is

a) 200 V
b) 250 V
c) 500 V

Answer 1

Given that,

Distance = 4 cm

Voltage on first plate = 300 V

Voltage on second plate = -100

Suppose, option d is 300 V.

We need to calculate the electric field

Using formula of electric field

$\Delta V=Ed$

$E=\dfrac{\Delta V}{d}$

Put the value into the formula

$E=\dfrac{300-(-100)}{4\times10^{-2}}$

$E=10000\ V/m$

We need to calculate the voltage at 3 cm distance from the second plate

Using formula of voltage

$V=Ed$

Put the value into the formula

$V=10^{4}\times3\times10^{-2}$

$V=300\ V$

Hence, The voltage at 3 cm distance from the second plate is 300 V.

(d) is correct option