Question

One of the following the silicon conductor that has the largest resistance is:

Select one:
long, thick and hot
short, thick and hot
short, thick and cold
long, thin and hot
long, thin and cold

Answer 1

The silicon conductor that has the largest resistance is long, thin and cold.

Reason and Concept:

Since silicon is a type of semiconductor, the temperature coefficient of resistance is negative. Therefore, the resistance is indirectly proportional to temperature.

That's why the resistance decreases with increase in temperature.

So, to have a large resistance (according to question), temperature should be low i.e. cold (due to inverse relation). Which means it's either short, thick and cold OR long, thin and cold while other options have hot (so not considered).

Now, taking the relation for semiconductors;

To have a large resistance (R), length (l) should be long (due to direct relation).

To have a large resistance (R), Area (A) should be small or thin (due to inverse relation).

That's why the correct answer is long, thin and cold.