# physics

A circular coil with a radius of 25 cm has 20 turns. The coil is oriented
perpendicularly to a magnetic field whose initial magnitude is 3.2 T.
Suddenly, the magnetic field vanishes in 0.4 s.
a. What is the initial magnetic flux in the coil?
b. What is the induced emf in the coil?
c. If the net resistance of the coil is 6.8 Ù what is the
magnitude of the induced current in the coil?
d. What is the direction of the induced current in the coil?
e. What is the rate of thermal energy generated by the coil?

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