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 block of metal is heated directly by dissipating power in the intern

1.	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.
Answer» 0.5 s 1S 1.5 s 2s Answer :A

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