Question

Find out the electric field intensity between the two long charged plates shown in the figure? ($\sigma$ - Surface charge density)


​​​​​​​$[$1 Mark$]$

• A. $\frac{\sigma }{2{ϵ}_0}$
• B. $\frac{\sigma }{{ϵ}_0}$
• C. Zero
• D. $\frac{3\sigma }{2{ϵ}_0}$

Answer 1

The correct option is A $\frac{\sigma }{2{ϵ}_0}$


Electric field intensity at point $P$ due to plate $A$
is $E_A=\frac{\sigma }{2{ϵ}_0}$ towards right

Electric field intensity at point $P$ due to plate $B$ is
$E_B=\frac{2\sigma }{2{ϵ}_0}$ towards left

$\therefore$ Net electric field intensity at point $P$

$E_{net}=E_B-E_A$ towards left

$=\frac{\sigma }{{ϵ}_0}-\frac{\sigma }{2{ϵ}_0}$

$E_{net}=\frac{\sigma }{2{ϵ}_0}$ towards left

$\therefore$ option (a) is correct