Author Question: A coil is wrapped with 300 turns of wire on the perimeter of a square frame (side length = 20 cm). ... (Read 87 times)

skymedlock · **on:** Jul 28, 2018

A coil is wrapped with 300 turns of wire on the perimeter of a square frame (side length = 20 cm). Each turn has the same area as the frame, and the total resistance of the coil is 1.5 W. A uniform magnetic field perpendicular to the plane of the coil changes in magnitude at a constant rate from 0.50 T to 0.90 T in 2.0 s. What is the magnitude of the induced emf in the coil while the field is changing?
a. 2.4 V
b. 1.6 V
c. 3.2 V
d. 4.0 V
e. 8.4 V

Question 2

A rectangular wire loop (length = 60 cm, width = 40 cm) lies completely within a perpendicular and uniform magnetic field of magnitude of 0.5 T. If the length of the loop starts increasing at a rate of 20 mm/s at time t = 0, while the width is decreasing at the same rate, what is the magnitude of the induced emf at time t = 4.0 s?
a. 6.8 mV
b. 5.2 mV
c. 3.6 mV
d. 8.4 mV
e. 10 mV