Question

In nature, hot air tends to rise and cool air tends to sink. This is behind the concept of convection heating that is used in ovens. Convection currents occur only in fluids such as liquids and gases but not in solids. Which of the examples below is an example of convection? A) rubbing your hands together. B) heating a fish tank. C) basking in the sun. D) striking a match.

Answer 1

The example of convection is (B) heating of     fish tank.

Explanation:

• Convection is the transfer of heat by the movement of a fluid (liquid or gas) between areas of different temperature . Warm air is less dense than cooled air and so convection currents can form in the presence of a temperature gradient.
• In simple words convection is a circular motion that happens when warmer air or liquid -which has faster moving molecule that make it less dense rises while cool the denser one drops down .Convection is a major factor in resulting wind or other factor of weather
• Here heating of fish tank is an example of convection.          

Answer 2

Answer is Option "B"

Explanation:

• MODES OF HEAT TRANSFER

         1) Conduction: This type of heat transfer happens when there is direct contact between the two object

        2) Convection: This type of heat transfer happens when there is a movement of fluid (liquid or gas)

        3) Radiation: This type of heat transfer happens when there is direct transfer of energy through space and then Hot liquid tends to rise and cool liquid tends to sink and thus the fish tank heats

• Hence, the right answer is option B "heating a fish tank"