Heat

Heat is a form of energy that moves from a warmer object to a cooler one until both reach the same temperature.

Imagine standing near a campfire, holding a metal skewer with a marshmallow, and noticing how different parts of your body heat up in different ways.

It all comes down to three methods of heat transfer: conduction, convection, and radiation.

Conduction occurs when heat transfers through direct contact.

In this case, your hand gets hot from holding the metal skewer, which is conduction.

Convection happens when heat moves through air or liquids.

Warm air rises near the campfire, and cooler air moves in to replace it. This ongoing movement creates a cycle called a convection current.

You feel the swirling hot air around you because of this convection.

Radiation also plays a role. It allows heat to travel in waves, like the warmth you feel while sitting near a campfire.

You feel the heat on your face from the glowing fire. Even if you're not very close, that's radiation.