A metal cylindrical bar (PQ) of length l, sectional area A, mass density ρᵐ and resistance R slides along the metal rails without friction in the presence of a magnetic field uniform B = Bo yˆwhich is directed upwards (perpendicular to the horizontal plane) as shown in the figure. At time t = 0, the bar moves in the + x direction with velocity from v0. The rails are of negligible strength. Consider that the length l of the bar is equal to the distance between the rails in contact. a) Calculate the magnitude and direction of the induced current in the bus. b) Calculate the speed of the bar as a function of time. c) Calculate the electrical power dissipated in the rod and the rate of decrease in kinetic energy of the rod.

A metal cylindrical bar (PQ) of length l, sectional area A, mass density ρᵐ and resistance R slides along the metal rails without friction in the presence of a magnetic field uniform B = Bo yˆwhich is directed upwards (perpendicular to the horizontal plane) as shown in the figure. At time t = 0, the bar moves in the + x direction with velocity from v0. The rails are of negligible strength. Consider that the length l of the bar is equal to the distance between the rails in contact. a) Calculate the magnitude and direction of the induced current in the bus. b) Calculate the speed of the bar as a function of time. c) Calculate the electrical power dissipated in the rod and the rate of decrease in kinetic energy of the rod.