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Four identical electrical lamps are labe...

Four identical electrical lamps are labelled `1.5 V` `0.5 A` which describes the condition necessary for them to operate at normal brightness. A `12 V` battery of negligible internal resistance is connected to lamps as shon, then

A

The value of R for normal brightness of each lamp is `(3/4)Omega`

B

The value of R for normal brightness of each lamp is `(21/4)Omega`

C

Total power dissipated in circuit when all lamps are normally bright is 24W.

D

Power dissipated in R is 21 W when all lamps are normally bright

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The correct Answer is:
B
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