iGCSE Thermal Energy

What is the method of heat transfer through a solid known as?

• conduction

• convection

• radiation

• all of the above

Which of the following materials is a good conductor of heat?

• wood

• plastic

• copper

• glass

What is the method of heat transfer in a fluid known as?

• conduction

• convection

• radiation

• all of the above

How do double glazed windows prevent heat loss by conduction?

• They use thin sheets of glass.

• They fill the space between the panes of glass with a small amount of gas.

• Some countries use triple glazed windows.

• All of the above.

A convection current is established in a heated beaker of water when?

• cooler more dense water displaces warmer less dense water

• warmer water rises to the top

• warm more dense water falls to the bottom of the beaker of water

• all the water in the beaker mixes

Firemen direct people to crawl along the floor when there is a fire in a building. Why is this?

• The warmer less dense air is higher in the room and carries the smoke with it.

• The cooler more dense air rises to the top of the room.

• They can see the floor more easily for tripping hazards.

• The floor cannot catch fire.

Which of the following surfaces is the best absorber and emitter of heat?

• silver shiny surface

• white matt surface

• black shiny surface

• black matt surface

From which part of a house is the most heat lost?

• floor and walls

• windows and front door

• windows and roof

• walls and the back door

A chef is cooking a kebab using a metal skewer. The heat is conducted along the metal. Which of the following statements best describes what is happening inside the metal skewer?

• The heat is flowing up and down the metal.

• The atoms at the heated end gain energy and pass this on through vibrations.

• The skewer melts.

• The cold energy is transferred out of the metal due to the heat energy at one end.

Complete the following sentence: The hotter an object is

• the greater the amount of heat radiated.

• the redder the object will be.

• the smaller the object will be.

• the smaller the kinetic energy of the particles.