Final answer:
The induced emf in the coil when the magnetic field changes from 0.05T to 0.06T in 0.1s is -3 mV, as calculated using Faraday's law of electromagnetic induction and Lenz’s Law.
Step-by-step explanation:
The electromagnetic force (emf) can be calculated using Faraday’s law of electromagnetic induction, which relates the emf in a coil to the rate of change of magnetic flux through the coil. The formula is emf = -N (ΔΦ/Δt), where N is the number of turns in the coil, ΔΦ is the change in magnetic flux and Δt is the change in time.
In this case, the change in magnetic flux, ΔΦ, is given by the change in magnetic field strength times the area of the coil, that is ΔΦ = B * A. If we substitute the given values, we have ΔΦ = ( 0.06T - 0.05T) * 0.0015m² = 0.000015 T*m². The change in time, Δt, is 0.1s. Hence the induced emf would be emf = -20 *(0.000015 T*m² / 0.1s) = -0.003 V or -3 mV. The negative sign indicates that the induced emf opposes the change in magnetic flux, as per Lenz's Law.
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