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NTA Abhyas JEE Main2020PhysicsAlternating CurrentPractice

The RMS value of AC which when passed through a resistor produces heat, which is twice that produced by a steady current of 1.414 A in the same resistor is

Options

  1. A2 A
  2. B3.46 A
  3. C2.818 A
  4. D1.732 A

Correct answer

A. 2 A

Step-by-step solution

It is given that the amount of heat produced by AC current is twice of the amount of heat produced by DC current. I = 1.414   A ∴     I r m s 2 ⋅ R = 2 × I 2 R I r m s 2 = 2 × 1.414 2 = 2 × 2 ⇒     I r m s = 2   A

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