wunder beta

🔥 Conduction, Convection, and Radiation

Explore the three ways heat travels, by contact, by moving fluids, and by invisible infrared waves, and learn to tell them apart in everyday life.

lessons

~15 min

to learn

🔬 Science

subject

Teens

level

Start the course →

What you’ll learn

ConductionExplain conduction as heat transfer by direct contact, strongest in solid metals.Heat always flows from hotter to cooler. Conduction transfers it through direct contact: heated particles vibrate faster and pass energy to their neighbours, without the material itself moving. It works best in solids, especially metals, while wood, plastic, and air are poor conductors called insulators.
ConvectionExplain convection as heat carried by a circulating fluid, where warm fluid rises and cool sinks.Convection transfers heat through fluids, meaning liquids and gases. Heated fluid expands, becomes less dense, and rises, while cooler fluid sinks to replace it, creating a circulating convection current. Radiators, boiling water, and the weather are all driven by convection currents.
RadiationExplain radiation as heat carried by infrared waves that need no medium, and compare all three modes.Radiation transfers heat as infrared electromagnetic waves, which need no material and can travel through empty space, as the Sun's warmth does to reach Earth. The three modes are easy to tell apart: conduction needs contact, convection needs a moving fluid, and radiation needs nothing at all.

Questions this course answers

How does conduction transfer heat?

Conduction transfers heat through direct contact, as vibrating particles pass energy to their neighbours.

Which is the best conductor of heat?

Metals are excellent conductors of heat, which is why a metal spoon in hot tea quickly feels hot.

In which does convection transfer heat?

Convection transfers heat in fluids, meaning liquids and gases, as warm fluid rises and cool fluid sinks.

Why does warm air rise in a convection current?

Heated air expands and becomes less dense, so it rises while cooler, denser air sinks.

What makes radiation different from conduction and convection?

Radiation carries heat as infrared waves and needs no medium, so it can travel through the vacuum of space.

How does the Sun's heat reach the Earth across empty space?

The Sun's heat reaches Earth by radiation, travelling as infrared waves that need no medium.

Grounded in trusted sources

BBC Bitesize
HyperPhysics
NASA

Every Wunder lesson is built from real, reputable sources — never invented.

Related Science courses

☕How a thermos keeps a drink hot 🍳How heat moves in a pan 🔩Conductors and Insulators ⚖️Conservation of Mass 🧲Contact and Non-Contact Forces 🪸Coral Bleaching and Ocean Acidification ⚡Current and Voltage 🎣Deep-Sea Creatures

Wunder is a personalized learn-anything platform — tell it any topic and it builds a beautiful, fact-checked course in minutes, with narration, a knowledge check, and a college-style University track.

Browse more Science courses · All topics · Home