A metal rod is pulled to the right with a constant velocity along two parallel m
ID: 1521591 • Letter: A
Question
A metal rod is pulled to the right with a constant velocity along two parallel metal rails connected with a strip of metal at one end, as shown in the diagram on the left. A magnetic field, B equal to 0.85 T points into the page. a) If the rails are separated by 47 cm and the speed of the rod is 79 cm/s to the right, a) What emf is generated? The magnetic field, B, is directed into the page b) If the rod has a resistance of 34 Ohm and the rails have negligible resistance, what is the current in the rod? c) Is the current induced into the above circuit flow in a clockwise or counter clockwise direction? d) What is the force generated by the above current?Explanation / Answer
a) Emf=vBL=0.79m/s*0.85T*0.47m=0.316 V
b) I=V/R=0.316V/34=9.29x0^-3 A
c) Since B is pointing into the page, by lenz law, the curent flows in counter clockwise direction.
d) F=I*L*B=9.29x0^-3 A*0.47m*0.85T=3.713x10^-3N