A metal bar of length L = 0.25 m slides freely on two frictionless, horizontal m
ID: 1373838 • Letter: A
Question
A metal bar of length L = 0.25 m slides freely on two frictionless, horizontal metal rails as shown in the figure below. The entire circuit has resistance R = 285 Ohm. A magnetic field B = 1.6 T is directed upward, perpendicular to the plane of the drawing and the rectangular area enclosed by the bars. An external force is applied to the bar such that it moves to the right with speed y = 26 m/s. What are the magnitude and direction of the current induced in the bar? magnitude A direction clockwiseExplanation / Answer
given,
length of the bar = 0.25 m
resistance = 285 ohm
magnetic field = 1.6 T
velocity = 26 m/s
induced emf = magnetic field * length * velocity
induced emf = 1.6 * 0.25 * 26
induced emf = 10.4 V
by ohm's law
V = I * R
10.4 = I * 285
I = 0.0365 A
current induced in the bar = 0.0365 A in the clockwise direction