Question

The electric field outside the plates of two oppositely charged plane sheets of charge density $\sigma$ is :

• A. $+\frac{\sigma }{2{\epsilon }_0}$
• B. $-\frac{\sigma }{2{\epsilon }_0}$
• C. Zero
• D. $\frac{\sigma }{{\epsilon }_0}$

Answer 1

The correct option is C Zero

The electric field due to charge plate is given by $E=\frac{\sigma }{2{ϵ}_0}$

The field lines outside the plates are equal and opposite so the field outside plates will be zero. i.e $E_{out}=\frac{\sigma }{2{ϵ}_0}-\frac{\sigma }{2{ϵ}_0}=0$

The field in between the plates will be $E_{in}=\frac{\sigma }{2{ϵ}_0}+\frac{\sigma }{2{ϵ}_0}=\frac{\sigma }{{ϵ}_0}$