Question

Two thin infinite parallel sheets have uniform surface densities of charge $+\sigma$ and $-\sigma$. Electric field in the space between the two sheets is :

• A. $\sigma /{\epsilon }_0$
• B. $\sigma /{2\epsilon }_0$
• C. $2\sigma /{\epsilon }_0$
• D. zero

Answer 1

The correct option is A $\sigma /{\epsilon }_0$

$E=E_1-E_2=\frac{\sigma }{2{\epsilon }_0}-\left(\frac{-\sigma }{2{\epsilon }_0}\right)=\frac{\sigma }{2{\epsilon }_0}=\sigma /{\epsilon }_0$
The field intensity in between sheets having equal and opposite uniform surface densities of charge becomes constant, i.e, an uniform electric field is produced and it is independent of the distance between the sheets.