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प्रश्न
- Assertion (A): An electron has a high potential energy when it is at a location associated with a more negative value of potential, and a low potential energy when at a location associated with a more positive potential.
- Reason (R): Electrons move from a region of higher potential to region of lower potential.
Select the most appropriate answer from the options given below:
पर्याय
Both A and R are true and R is the correct explanation of A.
Both A and R are true but R is not the correct explanation of A.
A is true but R is false.
A is false and R is also false.
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उत्तर
A is true but R is false.
Explanation:
When an electron is at a location associated with a negative value of potential, say -V, its potential energy is U = (-e)(-V) = eV. When an electron is at a location associated with a positive potential, say +V, its potential energy is U = (-e)(+V) = -eV. So, the assertion is true.
From higher to lower potential, current flows. Conventionally, electrons move from a lower to a greater potential when they flow in the opposite manner. So, the reason is false.
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