A closed loop of wire in an isolating coating is wrapped around in a form of an

Question

A closed loop of wire in an isolating coating is wrapped around in a form of an (deformed) “8” as shown in the figure (the coating prevents the wires from touching each other at the point of crossing). The loop is placed in a uniform magnetic field perpendicular to plane of loop which changes with time according to the formula B(t) = B0 exp(-t/) with B0=0.02T and =0.1s. The areas covered by the loops are S1=25cm2 and S2=15cm2, respectively. What is the EMF induced the wire? If the total resistance of the wire is R=2 what is the magnitude and direction of the induced current?

Explanation / Answer

B(t) = B0 exp(-t/), B0 = 0.02 T, = 0.1s. S1 = 25 cm2, S2 = 15 cm2, R = 2

the EMF induced the wire U = (S1 - S2)*|dB(t)/dt| = (S1 - S2)*B0/ *exp(-t/) = 2.0*10-4*exp(-10t) V

the magnitude of the induced current = U/R = 1.0*10-4*exp(-10t) A

direction: to the left on the uppermost line

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.