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A coil develops heat of 800 cal / sec . ...

A coil develops heat of 800 cal / sec . When 20 volts is applied across its ends. The resistance of the coil is (1 cal = 4.2 joule )

A

`1.2Omega`

B

`1.4Omega`

C

`0.12Omega`

D

`0.14Omega`

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