Conduction | MCQs

Explanation

A thermos flask is designed to reduce heat transfer through all three methods:

• Conduction: The flask has a vacuum insulation, which eliminates conduction through the container.
• Convection: The flask's design and vacuum insulation prevent convective heat transfer.
• Radiation: The flask's reflective coating minimizes radiant heat transfer.

Explanation

The cooling fins at the back of a refrigerator are typically made of a black, rough surface to maximize heat radiation. This design:

• Increases the surface area for heat transfer
• Absorbs heat from the surrounding air
• Emits heat more efficiently due to the rough surface

Explanation

• Heat is a form of energy associated with the motion of molecules in a substance.
• As molecules vibrate, rotate, and collide, they transfer energy from one another, resulting in the sensation of heat.

Explanation

In solids, heat transfer occurs primarily through conduction, where vibrations and collisions of particles (atoms or molecules) transfer energy from one point to another.

Explanation

• Conduction is the transfer of internal energy (heat) through direct contact between particles or molecules.
• Including collisions and movements of electrons within a substance.
• This process occurs in solids.

Explanation

• A thermal conductor is a material that allows heat energy to flow through it easily.
• Such as metals like copper, aluminum, and iron.