Question

A charge Q is uniformly spread over one surface of a very large nonconducting square elastic sheet having sides of length d. At a point P that is 1.25 cm outside the sheet, the magnitude of the electric field due to the sheet is E. If the sheet is now stretched so that its sides have length 2d, what is the magnitude of the electric field at P? 4E B) 2E C) E E/2 E/4

Answer 1

The new electric field at point P is E/4.

Step-by-step explanation:

It is given that,

The magnitude of electric field due to the sheet is E at a point P. The electric field due to a non conducting sheet is given by :

`E=(q)/(2A\epsilon_o)`

A is the area of square sheet

For the square sheet,
`A=d^2`, l is the side of square

`E=(q)/(2d^2\epsilon_o)`...........(1)

If the sheet is now stretched so that its sides have length 2d, electric field is E'

`E'=(q)/(2(2d)^2\epsilon_o)`.........(2)

Taking ratios of equation (1) and (2) as :

`(E)/(E')=(4)/(1)`

`E'=(E)/(4)`

If the sheet is now stretched so that its sides have length 2d, the new electric field at point P is E/4.