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Question
In a coil of resistance 100 Ω a current is induced by changing the magnetic flux through it. The variation of current with time is shown in the figure. The magnitude of change in flux through the coil is ______.
Options
200 Wb
275 Wb
225 Wb
250 Wb
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Solution
In a coil of resistance 100 Ω a current is induced by changing the magnetic flux through it. The variation of current with time is shown in the figure. The magnitude of change in flux through the coil is 250 Wb.
Explanation:
e = `(ΔPhi)/(Δt), I = 1/R(ΔPhi)/(Δt)`
I Δt = `(ΔPhi)/R` = Area under l - t graph, R = 100 ohm
∴ ΔΦ = `100 xx 1/2 xx 10 xx 0.5 = 250` Wb
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