Question

In the figure, a very large plane sheet of positive charge is shown. $P_1$ and $P_2$ are two points at distance $l$ and $2l$ from the charge distribution. If $σ$ is the surface charge density, then the magnitude of electric fields $E_1$ and $E_2$ and $P_1$ and $P_2$ respectively are

• A. $E_1 = \frac {σ}{ε_0}, E_2 = \frac {σ}{2ε_0}$
• B. $E_1 = \frac {2σ}{ε_0}, E_2 = \frac {σ}{ε_0}$
• C. $E_1 = E_2 = \frac {σ}{2ε_0}$
• D. $E_1 = E_2 = \frac {σ}{ε_0}$

Answer 1

Answer: (C)

$E_1 = E_2 = \frac {σ}{2ε_0}$

Answer 2

For an infinite charged plane
$E = \frac {σ}{2ε_0}$
for each value of distance l
$E_1 = \frac {σ}{2ε_0}$

$E_2 = \frac {σ}{2ε_0}$
Thus,
$E_1 = E_2 = \frac {σ}{2ε_0}$

So, the correct option is (C): $E_1 = E_2 = \frac {σ}{2ε_0}$