HEAT TRANSFER

1. We feel the heat from the handle of a metal pan because heat is transferred from the handle to our hand by___.

• a. radiation

• b. convection

• c. dispersion

• d. conduction

2. Which of the following situations happen because of convection?

• a. Heat from the sand is felt by the person walking on the beach

• b. Heat from the sun felt by a person lying on the beach

• c. Sea breeze felt by a person sitting by the beach

• d. Clouds forming over the beach

3. Which of the following situations illustrates radiation?

• a. Ironing of clothes

• b. Boiling water

• c. campers around a campfire

• d. spoon in a cup of hot coffee

4. Which of the following explains why the lady is able to hold the handle of the pan with her bare hands?

i. The handle is made of good insulator of heat

ii. The handle has low thermal conductivity

• a. I only

• b. I and II

• c. II only

• d. neither I nor II

5. Why are cooking utensils provide with wooden handles?

• a. Wood are cheaper than steel

• b. Wood is light and easy to handle

• c. Wood is poor conductor of heat.

• d. Wood is more attractive than steel.

6. Which of the following conditions happens because of conduction?

• a. Heat from the sand felt by person walking on the beach

• b. Heat from the sun felt by the person lying on the beach

• c. Sea breeze felt by person sitting on the beach

• d. Clouds forming over the beach

7. What happens when if two objects at different temperature are touching?

• a. No thermal energy transfer takes place.

• b. Thermal energy transfer from cooler objects to warmer objects.

• c. Thermal energy transfer from warmer objects to cooler objects.

• d. Thermal energy transfers regardless of objects temperature.

8. How is air being heated in the atmosphere?

• a. by conduction

• b. by radiation

• c. by convection

• d. any of the methods

9. Why do you use blanket while sleeping during night time?

• a. To slow down the transfer of your body heat to the surroundings.

• b. To prevent the coldness of the surroundings to reach your body.

• c. To feel comfortable.

• d. To sleep tight.

10. You can hold your fingers beside the candle flame without harm, but not above the flame. Why?

• a. Heat travels up by convection. Air is a poor conductor, so very little heat travels sideways.

• b. Heat travels up by conduction. Air is a poor conductor, so very little heat travels sideways.

• c. Heat travels up by radiation. Air is a poor conductor, so very little heat travels sideways.

• d. Heat travels up by flame. Air is a poor conductor, so very little heat travels sideways.