Resistance of a material always decreases if:
Correct answer: A. Temperature of the material is decreased
- A. Temperature of the material is decreased
- B. Temperature of the material is increased
- C. Number of free electrons available becomes more
- D. None of the above options is correct
Explanation
a) Temperature of the material is decreased:Correct! The resistance of a material decreases when its temperature is decreased. This phenomenon is observed in materials with positive temperature coefficients, like most metals. When the temperature decreases, the atoms in the material vibrate less, which leads to reduced collisions between electrons and atoms. As a result, there is less resistance to the flow of electric current.
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About Current Electricity
Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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