A protons speed as it passes point A is v It follows the tra

A proton\'s speed as it passes point A is v. It follows the trajectory shown in the figure. What is the proton\'s speed at point B?

Solution

Change in Kinetic energy = change in potential energy.

1/2 m( v²_f-v²_i) = Vq

Here V= 30+10 =40V

q= 1.6 *10^-19

m=1.67*10^-27 kg

Here v_i =v

Here value of v is not given. On substituting these values in above formula we can derive velocity of proton at point B or final velocity.