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Gravitation

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Gravitation:

Gravitation is the force of attraction between any two objects (having mass) in the universe.

Universal Law of Gravitation:

It states that “the Gravitational force is directly proportional to the product of the masses and inversely proportional to the square of the distance between them”.

Universal Gravitational Constant:

It is a constant represented by “G”, whose value is 6.673*10-11 N m2kg-2.

Free Fall:

When an object falls freely under the influence of gravitational force only then such objects are said to have free fall.

Acceleration Due To Gravity:

Acceleration during free fall is called acceleration due to gravity. Or it can also define as the acceleration caused by the force of gravity only.

Mass:

Most of the students got confused between mass and weight. Mass is a constant quantity that does not depend on geography, it is the measure of the inertia of an object. Its SI unit is Kg.

Inertia:

It is the tendency of an object to resist change in its state (rest or motion).

Weight:

It is the force by which Earth attracts an object towards it. Its SI unit is Newton.

Thrust:

It is a force that acts normally (perpendicularly) on an object. Its SI unit is Newton.

Pressure:

It is defined as the force (thrust) that acts on a unit area. It shows the effect of the thrust on an object. Its SI unit is Newton per meter2.

Pressure in Fluid:

As solid exerts pressure because of its mass, fluid also exerts pressure.

Buoyancy:

The upward force that acts on an object that is immersed in a fluid is called Buoyant force, and this phenomenon is called Buoyancy. The magnitude of the force depends on the density of the fluid.

Archimedes’ Principle:

It states that, “The upward force (buoyant force) acting on an object immersed fully or partially in a fluid is equal to the weight of the fluid displaced by the object.”

Relative Density:

It is the ratio of the density of a substance to the density of water. Since it is a ratio so it does not have any unit.

Density:

It is defined as the mass per unit volume. It is the amount of mass of a substance present in unit volume.