Question 21

A conducting sphere of radius 10 cm has an unknown charge. If the electric field 20 cm from the centre of the sphere is 1.5 × 10^{3} N/C and points radially inward, what is the net charge on the sphere?

Answer

Electric field intensity (E) at a distance (d) from the centre of a sphere containing net charge q is given by the relation,

Where, q = Net charge = 1.5 × 10^{3} N/C

d = Distance from the centre = 20 cm = 0.2 m

∈0 = Permittivity of free space

And,

= 9 × 10^{9} N m^{2} C^{−2}

∴

= 6.67 × 10^{9} C

= 6.67 nC

Therefore, the net charge on the sphere is 6.67 nC.

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Rasbir
2019-06-09 16:15:35

Please excuse me, I have recently found a mistake in the answer. It is written... Where,q=net charge=1.5*10Â³N/C. Here, 1.5*10Â³ is the value of E(electric field intensity.

Aman tiwari
2019-05-03 12:02:07

Very helpful appðððð

Gopika
2019-02-22 11:16:30

I love this app

Yung presix
2019-02-11 01:11:28

Thanks

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