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Question
A graph between the magnitude of the magnetic flux linked with a closed-loop and time is given in the figure. Arrange the regions of the graph in ascending order of the magnitude of induced emf in the loop.
Solution
induced emf ε = `(- "d" phi_"B")/"dt"`
i) Φ – t graph at ab is a straight line
∴ `("d"phi)/"dt"` = constant
∴ ε = -ve and constant
ii) Φ – t graph at bc, Φ is constant
∴ ε = 0
iii) Φ – t graph at cd is a straight line
`("d"ϕ)/"dt"` = constant
∴ ε = true and constant
iv) ab, bc, cd are ascending order of the magnitude of induced emf.
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