The kinetic energy of a charged particle decreases by 10 J as it moves from a point at potential 100V to a point at potential 200V. Find the charge on the particle.

Given: Change in Kinetic Energy of a charged particle: ΔE = 10 J
Potential difference : dV = 200-100 =100 V
We know that, when energy of a body is changed, work is being done.
Change in kinetic energy = Work Done
Thus, Work done : W = 10 J
Also Work is given as:
W = dV× q
Here dV is the potential difference and q is the charge of the particle.
Substituting the values:

Hence the charge on the particle is 0.1 C


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