A conducting rod AB moves parallel to x-axis in the x-y plane. A uniform magnetic field B pointing normally out of the plane exists throughout the region. A force F acts perpendicular to the rod, so that the rod moves with uniform velocity v. The force F is given by (neglect resistance of all the wires)
A. `(vB^(2)l^(2))/(R)e^(-t//RC)`
B. `(vB^(2)l^(2))/(R)`
C. `(vB^(2)l^(2))/(R)(1-e^(-t//RC))`
D. `(vB^(2)l^(2))/(R)(1-e^(-2t//RC))`
