Bubbles coming out of fishes that swim in deep Water keep increasing in size as
they rise upward. find out the reason.
Answers
Answer:
Fish can breathe underwater because their gills go intake and outtake and they have a little box inside them and then the water comes through the gills and water turns into oxygen.
Answer:
Have you ever thought about why most fishes never sink to the bottom of the ocean or float to the water’s surface? How is it that they can stay so perfectly buoyant underwater? You might be surprised to hear most bony fishes have a special organ to help them with that: a swim bladder. This is a thin-walled sac located inside the body of a fish that is usually filled with gas. Besides helping fishes stay buoyant it can also function as a sound producer and receptor or as an accessory respiratory organ. Wonder how a swim bladder works? Try this activity to find out!
Background
You probably know objects can sink or float when placed into water. In both cases the water moves out of the way, or is displaced, to make space for the object. An ancient Greek scientist named Archimedes discovered this principle of buoyancy. In physics buoyancy is an “upward force that pushes on an object that is immersed in a liquid.” If you have ever tried to push a beach ball underwater, you have felt this buoyancy force in action. The ball seems to push back up although you are pushing it down! Archimedes also discovered the strength of the upward acting force exerted by the liquid is equal to the amount of water displaced by an object. At the same time the volume of displaced water is always the same as the volume of a submerged object. This is why the water-displacement method is a great way to determine the volume of an irregularly shaped object.
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Whether an object sinks or floats is dependent on which force is larger: the force of gravity pulling down on the object (its weight) or the buoyancy force pushing up on it. If the buoyancy force is larger than the object’s weight, it will float on the water’s surface. If the object’s weight exceeds the buoyancy force, however, it will sink to the bottom. When the buoyancy force is exactly the same as the object’s weight, the object has neutral buoyancy and remains at its level. This means the object’s density becomes important as well. Dense objects have a high mass and only displace a low volume of water; they have a large mass-to-volume ratio. If an object has a small mass but displaces a lot of water, it is less dense and therefore has a low mass-to-volume ratio. Objects denser than water will sink whereas those less dense than water will float.
What does all this have to do with a swim bladder? For a fish to be buoyant, or float, it must displace an equal or greater amount of water than its own body mass. The trick is the swim bladder, which is basically like an air-inflated balloon that can expand and contract depending on how much gas is inside. When the swim bladder expands it will increase in volume and therefore displace more water. This increases the fish’s buoyancy and it will float upward. When the swim bladder deflates the fish’s buoyancy decreases and it will sink as it displaces less water. Divers use the same concept for their buoyancy-control devices