A metallic rod AB of length 1.5 m is made to move in a uniform magnetic field of 2 tesla with a velocity of 2 m/s as shown in figure. Then electro static field that appears in the rod is

Due to the action of magnetic force −eV→×B→, free electron in the rod migrate to the end B and the rod becomes polarized. As a result an electro static field appears in the rod and net Lorentz force on each free electron becomes zero. ∴−eE→+−eV→×B→=0 ⇒E→=−V→×B→=B→×V→ ⇒E = vB = 2×2 v/m = 4 v/m