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Convection:

The warm air is pushed up by the cold air underneath it. Same as buoyant force! This is where the term “heat rises” comes from.

Then the hot air cools and cycles down.

Radiation:

Infrared heat. Wavelengths that are longer than visible light.

The emissivaty of 1 radiates a lot (like a black surface). Emissivaty of 0 radiates nothing.

Example of a PV (pressure/volume) diagram

No matter what path is taken to the second state, it always ends up at the same pressure and volume

The system and surrounds

Make sure to convert all the units

Another useful conversion:

Since energy has left the system, the temperature has gone down.

The gas is doing work on the environment. The work done is the area under the curve.

(V_1) is initial volume and (V_2) is final volume.

Because the volume is not changing, there isn’t any work done on the gas or by the gas.

(C_V) is the molar specific heat.