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Question
The magnetic flux through a loop is varying according to a relation `phi = 6t^2 + 7t + 1` where `phi` is in milliweber and t is in second. What is the e.m.f. induced in the loop at t = 2 second?
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Solution
Given : `phi = 6t^2 + 7t + 1` (in milliweber),t=2s
find: Magnitude of induced e.m.f. (e)
formula: `e=(dphi)/dt` (in magnitude)
Calculation: Using formula
`e=d/dt(6t^2+7t+1)`
`=12t+7`
At t=2s
`|e|=12 xx 2 + 7`
`=31mV=31xx10^-3V`
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