An electron falls from rest through a vertical distance h in a uniform and vertically upward directed electric field E. The direction of electric field is now reversed, keeping its magnitude the same. A proton is allowed to fall from rest in it through the same vertical distance h. The time of fall of the electron, in comparison to the time of fall of the proton is
Smaller
5 times greater
Equal
10 times greater
A square loop ABCD, carrying a current I2, is placed near and coplanar with a long straight conductor XY carrying a current I1, as shown in figure. The net force on the loop will be
Two concentric conducting spherical shells A and B having radii rA and rB (rB > rA) are charged to QA and -QB . The electric field along a line passing through the centre is