Question

The number of electrons to be put on a spherical conductor of radius 0.1 m to produce an electric field of 0.036 N/C just above its surface is ____________.

Options

• 2.7 x 10⁵

• 2.6 x 10⁵

• 2.5 x 10⁵

• 2.4 x 10⁵

Answer 1

The number of electrons to be put on a spherical conductor of radius 0.1 m to produce an electric field of 0.036 N/C just above its surface is 2.5 x 10⁵.

Explanation:

`"E" = 1/(4pi epsilon_0). "ne"/"r"^2`

`therefore  "n" = "Er"^2/e. 4piepsilon_0`

`"n" = (0.036 xx 0.1 xx 0.1)/(9 xx 10^9 xx 1.6 xx 10^-19)`

`= 360/144 xx 10^5`

`= 2.5 xx 10^5`