Two point charges q1 and q2 are fixed at a distance 3.0 cm as shown in the figure. A dust particle with mass and charge starts from rest at point 'a' and moves in a straight line to point ‘b’.
What is its speed v at point b (in m/s) ? (round off to nearest integer)
Applying conservation of mechanical energy
or
Here,
Hence,
And solving for v, we find, …(i)
Electric potential at
…(ii)
Electric potential at
…(iii)
From (i), (ii) and (iii) we get
rounding off to nearest integer