The difference in the variation of resistance with temperature in a metal and a semiconductor arises essentially due to the difference in the

Options

A. crystal structure
B. change in the number of charge career
C. type of bonding
D. none of these

Answer

To solve the question regarding the difference in the variation of resistance with temperature in metals and semiconductors, we can break it down step by step.

### Step 1: Understand the Concept of Resistance
Resistance in a material is influenced by the movement of charge carriers (electrons in metals and holes/electrons in semiconductors). As temperature changes, the behavior of these charge carriers also changes.

**Hint:** Recall that resistance is related to how easily charge carriers can move through a material.

### Step 2: Analyze Metals
In metals, as the temperature increases, the lattice structure of the metal atoms vibrates more vigorously. This increased vibration leads to more frequent collisions between the charge carriers (electrons) and the vibrating atoms, which results in an increase in resistance.

**Hint:** Think about how increased atomic vibrations affect electron movement in metals.

### Step 3: Analyze Semiconductors
In semiconductors, the situation is different. As temperature increases, more electrons gain enough energy to jump from the valence band to the conduction band, thereby increasing the number of charge carriers (both electrons and holes). This increase in charge carriers leads to a decrease in resistance.

**Hint:** Consider how the energy levels in semiconductors allow for more charge carriers at higher temperatures.

### Step 4: Compare the Two
The key difference in the variation of resistance with temperature between metals and semiconductors is due to the change in the number of charge carriers. In metals, resistance increases with temperature due to increased collisions. In semiconductors, resistance decreases with temperature due to an increase in the number of charge carriers.

**Hint:** Focus on how the behavior of charge carriers in both materials changes with temperature.

### Step 5: Conclusion
Thus, the difference in the variation of resistance with temperature in a metal and a semiconductor arises essentially due to the difference in the change in the number of charge carriers with temperature.

### Final Answer
The answer is: **Change in the number of charge carriers.**

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