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An electric field us applied to a semico...

An electric field us applied to a semiconductor.Let the number of charge carriers be n and the average drift speed be v.If the temperature is increased,

A

both n and v will increase

B

n will increase but v will decrease

C

v will increase but n will decrease

D

both n and v will decrease.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the effects of increasing temperature on the number of charge carriers (n) and their average drift speed (v) in a semiconductor. ### Step-by-Step Solution: 1. **Understanding Charge Carriers in Semiconductors**: - In semiconductors, charge carriers are typically electrons and holes. The number of charge carriers (n) is influenced by temperature. 2. **Effect of Temperature on Charge Carriers**: - When the temperature of a semiconductor is increased, more thermal energy is provided to the electrons. This energy can break the covalent bonds in the semiconductor lattice, leading to the generation of more free electrons and holes. - Therefore, as temperature increases, the number of charge carriers (n) increases. 3. **Effect of Temperature on Drift Speed**: - The average drift speed (v) of charge carriers is influenced by how often these carriers collide with the lattice atoms. - As the number of charge carriers increases (due to the breaking of covalent bonds), the probability of collisions between charge carriers and lattice atoms also increases. - More collisions result in a decrease in the average drift speed (v) because the carriers are impeded more frequently. 4. **Conclusion**: - From the analysis, we conclude that with an increase in temperature: - The number of charge carriers (n) increases. - The average drift speed (v) decreases. - Thus, the correct option is that "n will increase but v will decrease." ### Final Answer: - The correct option is: **n will increase but v will decrease.**
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