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A 103 turn circular coil of radius 2.05 cm is immersed in a uniform magnetic field that is perpendicular to the plane of the coil. Over an interval of 0.185 s, the magnetic field strength increases from 54.7mT to 94.1mT. Find the magnitude of the average emf Eₐᵥ induced in the coil during this time interval, in millivolts.

User Dyve
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Final answer:

The magnitude of the average emf Eₐᵥ induced in the coil during the interval is 6.62 millivolts.

Step-by-step explanation:

When a coil is subjected to a changing magnetic field, an electromotive force (emf) is induced within it, following Faraday's law of electromagnetic induction. The formula to compute the induced emf in a coil is given by ε = -NΔΦ/Δt, where ε represents the induced emf, N is the number of turns in the coil, ΔΦ denotes the change in magnetic flux, and Δt is the time interval.

Given that the coil has 103 turns and a radius of 2.05 cm, first, we need to determine the change in magnetic flux (∆Φ). As the magnetic field strength changes from 54.7 mT to 94.1 mT over a time interval of 0.185 s, the change in magnetic field (∆B) can be calculated as 94.1 mT - 54.7 mT = 39.4 mT.

The formula for the magnetic flux through a coil is Φ = BA, where B is the magnetic field strength and A is the area of the coil. As the coil is a circular one, the area A = πr^2, where r is the radius. Hence, the initial magnetic flux Φ₁ = π(2.05 cm)^2 * 54.7 mT and the final magnetic flux Φ₂ = π(2.05 cm)^2 * 94.1 mT.

Subtracting Φ₁ from Φ₂ gives us the change in magnetic flux (∆Φ). Finally, using the formula ε = -NΔΦ/Δt, where N = 103 turns and Δt = 0.185 s, we calculate the induced average emf Eₐᵥ. Upon computation, the average emf Eₐᵥ is found to be 6.62 millivolts.

User Rene Hernandez
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