Question 4

A spherical conductor of radius 12 cm has a charge of 1.6 x 10^{-7}C distributed uniformly on its surface. What is the electric field

(a) Inside the sphere

(b) Just outside the sphere

(c) At a point 18 cm from the centre of the sphere?

Answer

**(a)** Radius of the spherical conductor, r = 12 cm = 0.12 m

Charge is uniformly distributed over the conductor, q = 1.6 × 10 ^{-7} C

Electric field inside a spherical conductor is zero. This is because if there is field inside the conductor, then charges will move to neutralize it.

**(b)** Electric field E just outside the conductor is given by the relation,

Where,

= Permittivity of free space

Therefore, the electric field just outside the sphere is 10^{5} N C^{-1}

**(c)** Electric field at a point 18 m from the centre of the sphere = E1

Distance of the point from the centre, d = 18 cm = 0.18 m

Therefore, the electric field at a point 18 cm from the centre of the sphere is .

4.4 x 10^{4} N/C

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Manish mannu
2019-06-13 12:57:21

There is a minor mistake in 2nd solution. 9*10^9Nm^2/C^2

Poonamchand
2019-01-08 10:23:20

It can not be solved by using gauss law????

Priyas Kumar
2018-10-18 00:03:41

Thanku

Tuba Aqueel
2018-08-01 01:28:34

Tnk u so much for ur help

harsha
2018-05-09 13:08:25

It was very very helpful. Ty Saral studyðð

rah
2018-03-30 15:42:20

nice

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