Question

Good conductors of heat are also good conductors of electricity. State True or False.
(A) True
(B) False

Answer 1

To analyze the given statement we need to know the concept of how a substance conducts electricity or heat. So that we can compare both and say whether the given statement is true or false. A good conductor of heat may be a bad conductor of electricity.

Complete step by step solution:
The substances are classified as conductors and non-conductors based on their conductivity.
Heat conductors: The substance that allows heat to pass through them are called heat conductors. And the substances that do not allow heat to pass through them are called non-conductors of heat.
Heat is transferred within a substance when kinetic energy of atoms in the substance is vibrating within the substance and is transferred between the other atoms of the substance. Heat conduction of the material depends on the density of the material. Denser the material efficient heat conduction.
Electric conductors: The substance that allows electric charges (electricity) to pass through them are called heat conductors. And the substances that do not allow heat to pass through them are called non-conductors of electricity.
The free electrons in the substance are used to conduct the electricity. The free electrons carry the electric charges. If there is no free electrons the electric charges cannot be carried and there is no conduction of electricity.
For the conduction of heat we need the kinetic energy of atoms in the substance to vibrate within the substance. For conduction of electricity we need free electrons in the substance.
So, a good conductor of heat may be a good conductor of electricity or may not be a good conductor of electricity. It depends on the substance. It is not compulsory for a good conductor of heat to be a good conductor of electricity too. There are some substances which are good conductors of electricity which do not conduct electricity. Example mica, wood etc.
Hence the correct answer is option B.

Note:
The substance that does not conduct electricity or heat is known as insulators i.e. the non-conductors are also called as insulators. There are some substances that lie between conductors and insulators known as semiconductors which are not good insulators nor good conductors.