smoking
The two factors that affect density are mass and volume. Density is calculated by dividing an object's mass by its volume. Objects with more mass in a given volume will have a higher density.
volume and weight
The two factors that determine a material's density (such as that of wood) are its mass and volume.
Mass and volume.
One way to reduce the density of an object is to increase its volume while keeping the mass constant. Another way is to reduce the mass of the object while keeping the volume constant.
From the Universal Gas Law: PV/T = a constant, where P = gas pressure, V = gas volume, and T = gas temperature. I would say the two factors that determine volume are pressure and temperature.
The chest wall and the lung tissue recoil
There are two factors that affect gas pressure. These factors are temperature and volume. Higher volume means lower pressure. Higher temperature means higher pressure.
Mass and volume.
Its surface area and volume.
The two factors that determine a material's density are its mass and volume. Density is calculated by dividing an object's mass by its volume. Materials with more mass packed into a smaller volume will have higher density.
The density is the mass divided by the volume.