Question

A circular loop of flexible conducting wire has an initial circumference of 150cm. This loop is in a uniform 1.5 T magnetic field, which remains parallel to the loop's area vector. The loop begins to shrink, decreasing the circumference at a rate of 5 cm/s.

A) Calculate the EMF around the loop 4 seconds after it begins to shrink

B) Is the EMF increasing or decreasing with time?

C) Calculate the change in magnetic field required to keep the EMF zero in part A.

6. A circular loop of flexible conducting wire has an initial circumference of 150 cm. This loop is in a uniform 1.5-T magnetic field, which remains parallel to the loop's area vector. The loop begins to shrink, decreasing its circumference at a rate of 5 cm/s. l A. Calculate the induced EMF around the loop 4 seconds after it begins to shrink. (16 mV) B. Is the EMF increasing or decreasing with time? C. To keep a zero EMF along this loop, the magnetic field could also change. Calculate the change in magnetic field required to keep the EMF zero in part (A) (i.e. at 4 seconds).

Answer 1

1 o - ABT r dr C 2TY 2厅 -0.05M1 2M dr -Scmlp dt dt 2T 27 C= (10-6x) 2 חx After us 2T 0 15.X 10 V 2- (-2x15) (n) ( 2TT 24 = 15.6 mV So Enf de creane. decrease as 2 AT dr + O dt dt + (-7x12 ) 15.6 X10 2TT 0.115 TI C Increasioy dt