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Class 12
Physics
Electric Charges and Field
a conducting sphere of radius 10 cm has an unknown...

Question:
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 × 10³ 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 × 10³ N/C

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

∈0 = Permittivity of free space

And,

= 9 × 10⁹ N m² C⁻²

∴

= 6.67 × 10⁹ C

= 6.67 nC

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

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Question:
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 × 10³ N/C and points radially inward, what is the net charge on the sphere?

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Question: 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 × 103 N/C and points radially inward, what is the net charge on the sphere?

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Question:
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 × 10³ N/C and points radially inward, what is the net charge on the sphere?