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AP EAMCET · PHYSICS · Electromagnetic Induction

A magnetic field given by \(B(t)=\left(0.2 t-0.05 t^2\right) T\) is directed perpendicular to the plane of a circular coil containing 25 turns of radius \(1.8 \mathrm{~cm}\) and whose total resistance is \(5 \Omega\). The power dissipation at \(3 \mathrm{~s}\) is nearly

  1. A \(4 \mu \mathrm{W}\)
  2. B \(7 \mu \mathrm{W}\)
  3. C \(2.3 \mu \mathrm{W}\)
  4. D \(1.25 \mu \mathrm{W}\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(1.25 \mu \mathrm{W}\)

Step-by-step Solution

Detailed explanation

Given that, number of turns, \(N=25\) Radius of coil, \(r=1.8 \mathrm{~cm}=1.8 \times 10^{-2} \mathrm{~m}\) Resistance of coil, \(R=5 \Omega\) Magnetic field, \(B=\left(0.2 t-0.05 t^2\right) \mathrm{T}\) Now, area of coil,…