Semiconductors

Step 1: Concept
In a parallel diode configuration, the diode with the lower barrier voltage will conduct first, clamping the voltage across the other diode.
Step 2: Analysis
Ge barrier (0.3 V) < Si barrier (0.7 V). Therefore, the Ge diode will conduct and the Si diode will remain off.
Step 3: Calculation
. .
Step 4: Conclusion
Hence, the voltage is 23.7 V.
Final Answer:(A)

- Statement 1: Pure silicon doped with a trivalent impurity (such as boron) results in a p-type semiconductor, which has more holes as majority carriers. This statement is correct.
- Statement 2: In an n-type semiconductor, the majority carriers are electrons, not holes. This statement is also correct.
- Statement 3: In a p-type semiconductor, the majority carriers are holes, and the minority carriers are electrons. Therefore, this statement is correct.
- Statement 4: The resistivity of an intrinsic semiconductor decreases with an increase in temperature, which is incorrect. In intrinsic semiconductors, resistivity decreases as temperature increases due to an increase in charge carriers, making this statement the incorrect one.

The resistivity of a semiconductor decreases with an increase in temperature. As the temperature increases, more charge carriers are excited, leading to a decrease in resistivity. Therefore, the graph showing a downward curve as temperature increases best represents the behavior of resistivity in a typical semiconductor.