Item 3 Which statement describes the electrical conductivity of metals and semiconductors? Choose the correct answer.

Metals are poor conductors at low temperatures.

The conductivity of metals changes with changing pressure.

The conductivity of semiconductors changes with changing pressure.

Semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.

Semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.

Explanation:

A semiconductor can be defined as a crystalline solid substance that has its conductivity lying between that of a metal and an insulator, due to the effects of temperature or an addition of an impurity. Semiconductors are classified into two main categories;

1. Extrinsic semiconductor.

2. Intrinsic semiconductor.

The statement which best describes the electrical conductivity of metals and semiconductors is that semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.

This ultimately implies that, semiconductors are typically an insulator (poor conductor) at low temperatures and a good conductor at high temperatures.

Additionally, conduction involves the transfer of electric charge or thermal energy due to the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction.

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

i believe the answer is a.