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A block of metal is heated directly by d...

A block of metal is heated directly by dissipating power in the internal resistance of block. Because of temperature rise, the resistance increases exponentially with time and is given by `R(t)=0.5e^(2t)`, where t is in seconds. The block is connected across a 110 V source and dissipates 7644 J heat over a certain period of time. Calculate this period of time.

A

0.5 s

B

1s

C

1.5 s

D

2s

Text Solution

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The correct Answer is:
A
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