Because lighter stuff float but Heaver stuff don't
An object will float if it has less density than the fluid it is placed in.For example, in the specific case of water, some objects that will float on it is anything made from most woods and most plastics.
Those object which have low density then water like wood, ice etc. can flow and those with high density get sink..
Whether an object floats or sinks is a function of its relative density, to the medium in which it is placed. If the object is less dense, it floats, If it is more dense, it sinks. Density = Mass per unit Volume
Yes, adding salt to water increases its density, which can make some objects that would normally sink, like eggs, float. By altering the density of the water, the buoyant force exerted on the object can be increased to make it float.
Displacement is the action of pushing water aside when an object is placed in or on water. Even a small object will displace some water, causing it to move out of the way to accommodate the object. This principle is key in understanding how objects float in water.
It's far from clear what the actual question is. Some objects float in both salt and fresh water, some objects float in neither, and some objects float in one but not the other. Any object that floats in fresh water will float in salt water, but the reverse is not true.
Objects float or sink in a liquid based on their density compared to the density of the liquid. If the object's density is less than that of the liquid, it will float. If its density is greater, it will sink. Archimedes' principle states that the buoyant force acting on an object is equal to the weight of the fluid the object displaces.
Since density is proportional to it's mass and the ability to float is inversely proportional to it's volume, an object that's heavy will sink and an object that's light should float. An object that has some surface volume should float, while an object that has little surface volume should sink.
Materials float or sink depending on their density. If an object is less dense than the liquid it is placed in, it will float. If it is more dense, it will sink. The buoyant force acting on the object helps determine whether it will float or sink.
Some things float on water because they are less dense than water, creating buoyancy that allows them to stay afloat. Other things sink in water because they are denser than water, causing them to displace water and sink. Factors like shape, size, and weight can also affect whether something will float or sink in water.
A floating object has a density less than what it is floating in. If an object has more density than the medium it is placed in, the medium will be unable to hold the object. The object will, therefore, sink.
When the apparatus is placed in warm water, the water level in the apparatus is expected to decrease as the liquid inside the apparatus expands due to the increase in temperature. This expansion will cause some liquid to spill out and the water level to drop.