When you take a deep breath while floating on water, you will generally float more or experience increased buoyancy. This is because the act of taking a deep breath increases the volume of air in your lungs, which in turn increases your overall buoyancy.
When you float on water, the buoyant force acting on your body helps counteract the force of gravity. Buoyant force is determined by the density of the fluid (water, in this case) and the volume of the submerged portion of your body. According to Archimedes' principle, the buoyant force is equal to the weight of the fluid displaced by the submerged portion of your body.
By taking a deep breath, you increase the volume of air in your lungs, which effectively increases the volume of your body. Since the buoyant force depends on the volume of the submerged portion of your body, the increased volume due to the expanded lungs increases the buoyant force acting on you. As a result, you will experience greater upward force and float higher in the water.
It's important to note that the increase in buoyancy from taking a deep breath may vary depending on various factors, including body composition, lung capacity, and the overall distribution of mass in your body. Additionally, other factors such as body position and water conditions can also influence the floating behavior.