A circular loop of flexible iron wire has an initial circumference of 165.0cm, but its circumference is decreasing at a constant rate of 12.0cm/s due to a tangential pull on the wire. The loop is in a constant, uniform magnetic field oriented perpendicular to the plane of the loop of magnitude 0.500T.

0.005 V

Explanation:

We are given that

Initial circumference of circular loop=C=165 cm

Rate of circumference,

Magnetic field,B=0.5 T

We have to find the induced emf at time t=9 s

We know that induced amf,E=

Area of circular coil,A=

Circumference of circular coil,C=

Radius of coil at time t=9 s

E=

Magnitude of induced emf=0.005 V

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