What does an object float or sink when placed on the surface of water ?

Question

Answer

* An object sinks in water if its density is greater than that of water. * An object floats in water if its density is less than that of water.

Answer

An object floats if it's density is less than that of water (or) if it's relative density is less than 1.
An object sinks if it's density is more than that of water (or) if it's relative density is
more than 1.

Answer

Introduction:

When an object is placed on the surface of water, it can either float or sink. Whether an object floats or sinks depends on its density and the density of the liquid it is placed in. Density is the measure of how much mass is contained within a given volume. In this case, the density of the object is compared to the density of water.

Factors affecting floating and sinking:

Several factors determine whether an object will float or sink in water:

1. Density: Density is the most important factor in determining whether an object will float or sink. If the object's density is less than the density of water, it will float. If the object's density is greater than the density of water, it will sink.

2. Archimedes' Principle: Archimedes' principle states that an object immersed in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces. If the buoyant force is greater than or equal to the weight of the object, it will float. If the buoyant force is less than the weight of the object, it will sink.

3. Volume: The volume of an object also plays a role in determining whether it will float or sink. If the volume of the object is large relative to its weight, it is more likely to float.

Floating:

When an object floats on the surface of water, it means that its weight is balanced by the upward buoyant force exerted by the water. The buoyant force is equal to the weight of the water displaced by the submerged part of the object. If the buoyant force is greater than or equal to the weight of the object, the object will float.

Sinking:

When an object sinks in water, it means that its weight is greater than the upward buoyant force exerted by the water. The buoyant force is not enough to counteract the weight of the object, causing it to sink.

Examples:

1. Wooden block: A wooden block floats on water because its density is less than the density of water. The empty spaces within the wood make it less dense than water, causing it to float.

2. Iron nail: An iron nail sinks in water because its density is greater than the density of water. Iron is denser than water, so it sinks when placed on its surface.

3. Plastic bottle filled with air: A plastic bottle filled with air floats on water because the air inside the bottle decreases its overall density. The buoyant force exerted by the displaced water is greater than the weight of the bottle, allowing it to float.

Conclusion:

Whether an object floats or sinks in water is determined by its density and the density of water. If the object's density is less than water, it will float, and if it is greater, it will sink. Additionally, the buoyant force exerted by the water plays a crucial role in determining whether an object floats or sinks.

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