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An oil drop carrying a charge q has a ma...

An oil drop carrying a charge q has a mass m kg. it is falling freely in air with terminal speed v. the electric field required to make, the drop move upwards with the same speed is

A

`(mg)/(q)`

B

`(2mg)/(q)`

C

`(mgv)/(q^(2))`

D

`(2mgv)/(q)`

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The correct Answer is:
B
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