A 4.2 cm diameter circular loop of wire is in a 1.14 T magnetic field. The loop is removed from the field in 0.18 s. Assume that the loop is perpendicular to the magnetic field. What is the average induced emf?

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Given Information:Diameter of loop = d = 4.2 cm = 0.042 m

Magnetic field = B = 1.14 T

Time = Δt = 0.18 s

Required Information:EMF = ?

Answer:EMF = 0.417 V

Explanation:The Faraday’s Law of Induction relates induced EMF and the time rate of change of magnetic flux which is given by

EMF = -ΔФ/Δt

EMF = -AΔB/Δt

Where A is the area of circular loop and ΔB is the change in magnetic field

A = πr²

A = π(d/2)²

A = π(0.042/2)²

A = 0.0659 m²

EMF = -0.0659*(0 – 1.14)/0.18

EMF = -0.0659*(-1.14)/0.18

EMF = 0.417 V

Therefore, the average induced EMF in circular loop of wire is

0.417Volts