How can Boyle's law be applied to everyday life?
A basketball is held at a certain volume and pressure (constant temperature). When it hits the ground, the volume decreases and the pressure increases...and the increasing pressure springs the ball back up at you. THere is the issue of the elasticity of the rubber, but the decreasing volume - increasing pressure of the "bounce" is an application of Boyle's Law.
Boyle's Law states that for a fixed amount of gas, volume is inversely related to pressure. This is applicable in the respiratory system.
When you contract your respiratory muscles, you draw air into your lungs and by increasing the volume of your chest, you decrease the pressure of your chest.
When you exhale, you stop contracting your inspiratory muscles and because of the natural recoil of your lungs, your chest will become smaller. Hence, your volume will be reduced and the pressure of your lungs will increase. Since the pressure has increased, it will be higher than the atmospheric pressure outside. (the inside pressure in your chest is higher than the pressure outside your chest) Therefore, your air will move from your lungs into the atmosphere, allowing the pressure to be released.