Question 28: When two protons are brought close together, what happens to their potential energy? (Work, Power & Energy, interconversion of potential and kinetic energy)
Correct answer: B. P.E. increases
- A. Kinetic energy increases
- B. P.E. increases
- C. P.E. decreases
- D. P.E. does not change
Explanation
Correct Answer: (b) P.E. increases Explanation:Like charges repel each other, meaning a force pushes them apart.As you bring the protons closer, you need to do work against this repulsive force. This work done gets stored as potential energy in the system.Therefore, the closer the protons are, the stronger the repulsion and the higher their potential energy.Incorrect Options:(a) Kinetic energy increases: This could happen if the protons collide and bounce off each other, but it doesn't have to be the case. If the protons are brought close slowly, their kinetic energy might not change significantly.(c) P.E. decreases: This is the opposite of what happens due to the repulsive force.(d) P.E. does not change: The potential energy always changes when the positions of charged particles change relative to each other unless they are infinitely far apart.
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About Work and Energy
Work transfers energy when a force causes displacement, while kinetic energy, gravitational potential energy and power describe motion, position and the rate of energy transfer. The work-energy theorem links net work with change in kinetic energy, and efficiency accounts for energy losses rather than treating them as energy destruction.
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