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Most Important Selected Qs for JEE AdvancedPhysicsElectromagnetic Induction

A conducting disc of conductivity has a radius a and thickness t . If the magnetic field B is applied in a direction perpendicular to the plane of the disc, changes with time at the rate of d B d t = . Calculate the power dissipated (in mW ) in the disc due to the induced current. [Take : =2 ~T / s , a =1 ~cm , t =2 ~mm and = 4 10^8 ⁻¹ ~m ⁻¹ ]

Correct answer

4

Step-by-step solution

P = t 2 ^2 ₀^a r^3 d r= t a^4 8 ^2

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