Conduction
What is conduction?
The transfer of heat through direct contact.
What is convection?
The transfer of heat through the movement of liquids or gases.
What is radiation?
The transfer of heat through waves without touching.
What is heat?
Energy that moves from a warmer object to a cooler object.
Which type of heat transfer requires direct contact?
Conduction
Which type of material is usually a better conductor: metal or wood?
Metal
Does warm air rise or sink?
Rise
What is the biggest natural source of radiant heat for Earth?
The sun
Does heat move from hot to cold, or cold to hot?
Hot to cold
Which type of heat transfer happens in liquids and gases?
Convection
Why does a metal spoon feel hotter than a wooden spoon in hot soup?
Metal is a better conductor and heat moves through it easier
Why does steam rise from a pot of boiling water?
The warm water vapor rises because it is less dense.
Why can you feel heat from a fire without touching it?
Heat is travelling from the fire as waves through the air, that's radiation
What happens to particles when they are heated?
They move faster
Which type of heat transfer does NOT need matter?
Radiation
Why do tiles feel colder than carpet, even when they are the same temperature?
Carpet is a better insulator, making it easier to trap heat in your body. Heat moves from hot to cold so the cold tiles steal (conduct) your body heat
How does a convection oven cook food faster than a regular oven?
Hot air circulates around the food, spreading heat evenly.
Why does wearing dark clothing make you feel warmer in the sun?
Dark colours absorb more heat than light colours
Why does a balloon expand when heated?
The particles move faster and spread out.
Why are pot handles often made of plastic or rubber?
They are insulators and reduce heat transfer by conduction.
You want to heat a frying pan evenly and quickly on a stove. Why is conduction the best method of heat transfer in this situation?
The pan is in direct contact with the burner, allowing heat to move efficiently through the metal.
A classroom heater is placed near the floor. Why is convection the best way to heat the entire room?
Warm air rises and circulates, spreading heat throughout the room.
Astronauts feel heat from the Sun in space even though there is no air. Why is radiation the only heat transfer method that works there?
Radiation does not need matter or air to transfer heat.
Why does touching a cold metal pole in winter make your hand feel colder than touching wood?
Metal conducts heat away from your hand faster.
You are designing a thermos to keep soup hot. Which heat transfer methods must be reduced, and why?
Conduction, convection, and radiation must all be reduced to prevent heat loss.