PHYSICS

JAMB 2000 - Question 43

Physics 2000 JAMB Past Questions - Question 43: the magnetic flux in a coil having 200 turns changes at the time rate of 0.08wbs. the induced emf in the coil is

Choose the correct answers from the options given.
the magnetic flux in a coil having 200 turns changes at the time rate of 0.08wbs. the induced emf in the coil is
A:
B:
C:
D:
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Correct Answer

B

Explanation

E.M.F =N d0 /dt =200/0.08=16vTo calculate the induced electromotive force (emf) in a coil when the magnetic flux changes, you can use Faraday's law of electromagnetic induction, which states that the emf (E) induced in a coil is directly proportional to the rate of change of magnetic flux (dΦ/dt) passing through the coil. The formula is:

E = -N * (dΦ/dt)

Where:
E = Induced emf (volts)
N = Number of turns in the coil
dΦ/dt = Rate of change of magnetic flux (webers per second)

In your case:
N = 200 turns
dΦ/dt = 0.08 webers per second

Now, you can calculate the induced emf:

E = -200 * 0.08
E = -16 volts

The negative sign indicates that the induced emf will create a current in the coil that opposes the change in magnetic flux. So, the induced emf in the coil is 16 volts.