Two long parallel plates A and B are separated by a distance of 4 cm with an electric field of 45 . 5 Vm - 1 between the plates directed normally from plate A to plate B , as shown in the figure. An electron is projected from plate A with velocity v at an angle of 30 ° with the surface of plate A . The maximum value of v so that the electron does not hit plate B is ( Assume gravity free space, charge of electron

Step-by-step solution

The figure below represents the electron between two parallel plates A and B .... The expression for the maximum height is, h max = v 2   sin 2   30 ° 2   a 4 100 = v 2   sin 2   30 ° 2   a       . . . 1 The acceleration of the electron is, F = q e E m a = q e E a = q e E m Substitute the values in equation 1 . 4 100 = v 2   sin 2   30 ° 2   q e E m 4 100 = v 2   1 4 2   q e E m Rewrite the above equation. v = 4 × 8 100 q e E