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Question
The kinetic energy of a charged particle decreases by 10 J as it moves from a point at potential 100 V to a point at potential 200 V. Find the charge on the particle.
Solution
By work-energy theorem,
Change in K.E. = Amount of work done
Change in K.E. = 10 J
Let the charge on the particle be q.
Change in potential,
Work done = \[∆ V \times q\]
\[ \Rightarrow q = \frac{10}{100} = 0 . 1 C\]
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