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If the current flowing in the wire becomes double, then the amount of heat produced in the wire will become:

If the current flowing in the wire becomes double, then the amount of heat produced in the wire will become: Correct Answer Four times

CONCEPT:

Electrical energy:

  • The fact that conductors offer resistance to the flow of current, means that work must be done to maintain the current.
  • The amount of work done by current I, flowing through a wire is given as,


⇒ W = VIt = I2Rt

Where V = potential difference, R = resistance and t = time for which current is flowing

  • This work gets converted into the form of heat.


CALCULATION:

Given:

I1 = I, and I2 = 2I

  • When the current in the wire is I, the amount of heat produced is given as,

⇒ Q1 = I2Rt     -----(1)

  • When the current in the wire is 2I, the amount of heat produced is given as,

⇒ Q2 = (2I)2Rt

⇒ Q2 = 4I2Rt     -----(2)

By equation 1 and equation 2,

⇒ Q2 = 4Q1

  • Hence, option 1 is correct.

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