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A gold foil weighing 60 mg/cm^(2) is pl...

A gold foil weighing 60 mg/`cm^(2)` is places on a horizontal charged plate. What would be the density of charge so that the foil may just rise ?

A

`1.20 xx 10 ^(-6) C // m ^(2)`

B

`1.02 xx 10 ^(-6) C// m ^(2)`

C

`2 .02 xx 10 ^(-6) C//m ^(2)`

D

`2.20 xx 10 ^(-6) C // m ^(2)`

Text Solution

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The correct Answer is:
B
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