The inverse relationship between volume and pressure, known as Boyle’s law, states that as pressure increases, volume decreases, and vice versa, at constant temperature. This is because when pressure is applied to a gas, its molecules become closer together, reducing its volume. When pressure is released, the molecules spread out, increasing the volume. This law has practical applications in various fields, such as scuba diving, where understanding the effects of pressure on gas volume is crucial for safe diving operations.