Conduction Convection Radiation Quiz
Questions: 16 · 10 minutes
1. A hot drink is placed in a foam cup rather than a metal cup. Why does the foam generally help the drink stay hot longer?
Foam generates heat as it touches the drink.
Foam increases convection through the cup wall.
Foam reflects every form of thermal energy back into the drink.
Foam is a poor thermal conductor, so it slows energy transfer through the cup wall.
2. Air just above a floor heater warms, rises, and is replaced by cooler air. Which process creates this circulation?
Conduction
Condensation
Radiation only
Convection
3. A tile is heated at one end, but the tile itself does not flow or circulate. Energy gradually reaches the other end. Which mechanism dominates within the tile?
Radiation through a vacuum
Convection
Conduction
Evaporation
4. A reflective foil layer is installed in a roof space with its shiny surface facing an air gap. Which heat-transfer mechanism is it chiefly intended to reduce?
Conduction through solid roof supports
Convection caused by all air movement in the building
Radiation across the air gap
Evaporation from the roof surface
5. A heater warms air near the floor. Later, a lightweight ribbon hanging above the heater moves upward. What is the best explanation?
The ribbon conducts warm material downward into the heater.
Infrared radiation physically pushes the ribbon upward.
Cool air becomes less dense and rises from the heater.
Heated air becomes less dense and rises in a convection current.
6. A metal spoon becomes hot after being left in a bowl of hot soup. Which heat-transfer process mainly carries energy along the spoon?
Radiation through the spoon's interior
Convection within the metal
Conduction through the metal
Evaporation from the spoon
7. A metal bench and a wooden bench have been outdoors at the same temperature, but the metal feels colder to your hand. What best explains this?
Metal conducts energy away from your hand faster than wood does.
Metal must be at a lower temperature than the wood.
Wood sends more infrared radiation into your hand.
Convection occurs inside the solid metal but not inside wood.
8. In a pot of water heated from below, warmer water rises while cooler water sinks. Why does the warmer water tend to rise?
Heating makes the water more magnetic.
Radiation pushes the warmer water toward the surface.
The warmer water generally becomes less dense than the cooler surrounding water.
Conduction turns the warmer water into a solid.
9. At the particle level, how is thermal energy mainly transferred by conduction through a solid?
The entire solid circulates in a continuous current.
More energetic particles transfer energy to neighboring particles through interactions.
Visible light carries all the energy between adjacent particles.
Cold particles move through the solid toward the heat source.
10. Two identical containers are placed under the same heat lamp. One has a dull black surface and the other has a shiny silver surface. Which is most likely to absorb radiant energy more effectively?
The shiny silver container, because shiny surfaces absorb all wavelengths
The dull black container
Both containers, because surface finish does not affect radiation
Neither container, because heat lamps transfer energy only by convection
11. You can feel warmth from a campfire even when the air between you and the fire is cold. Which mechanism most directly explains the warmth traveling from the fire to you?
Conduction through the air
Infrared radiation emitted by the fire
A convection current moving only downward
Condensation on your skin
12. Which statement best describes convection?
Thermal energy is carried by the bulk movement of a liquid or gas.
Thermal energy passes through direct particle interactions without bulk movement.
Thermal energy travels only through empty space.
Thermal energy is created when a substance changes state.
13. Why are saucepan handles often made from wood or heat-resistant plastic rather than bare metal?
Those materials create convection currents that cool the food.
Those materials conduct thermal energy more slowly than most metals.
Those materials have a higher temperature than metal during cooking.
Those materials prevent the pan from emitting radiation.
14. On a sunny day, land often warms faster than nearby water. Air over the land rises, and cooler air moves in from over the water. What is this air movement an example of?
Conduction through the ground alone
Insulation caused by the coastline
Radiation transferring coolness from the water
A convection current caused by temperature and density differences
15. Which method of heat transfer can carry energy from the Sun to Earth through the vacuum of space?
Radiation
Convection
Conduction
Evaporation
16. A vacuum flask has a gap containing very little matter between its inner and outer walls. Which transfers are most directly reduced by this vacuum?
Conduction and convection, because both require matter
Radiation only, because conduction needs no matter
Convection only, because conduction occurs easily across a vacuum
Radiation and evaporation only