A gas when a fixed mass is compressed into a smaller volume then b) density increases.
Density is the measurement of how tightly a material is packed together. It is defined as the mass per unit volume. Density Symbol: D or ρ Density Formula: ρ = m/V, where ρ is the density, m is the mass of the object and V is the volume of the object.
Mass is the measure of object's inertia, more the mass more the inertia. It is a property of material , so it does not change with place. SI unit is 'kg'. It is a scalar quantity.
Volume is a three-dimensional quantity that is used to measure the capacity of a solid shape. It means the amount of three-dimensional space a closed figure can occupy is measured by its volume.
Density = mass / volume
if mass is fixed, then mass = constant
Density will be inversely related to volume
hence , on compression , volume get decreased but mass is constant hence , density will increase
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