Question

What is gravity?

Answer 1

Hint: Gravity explains the mysterious force that exists among all material objects in the universe. It is also known as gravitation. It explains why an object dropped from a height falls towards the earth and does not move upwards, what makes a planet to revolve around the sun or why does moon not fall to the earth.

Complete answer:
Gravity is a natural occurrence that we observe in our daily life. We always observe that an object dropped from a height falls towards the earth and does not move upwards. We also know that all the planets revolve around the Sun. The moon revolves around the earth. In all these cases, according to the law of inertia, there must be some force acting on the objects, the planets and on the moon which makes it possible. This force is known as the gravitational force. This phenomena which gives an idea about the existence of a force between any two objects is known as gravity. The force due to gravity is always attractive and acts along line joining the objects.

Additional Information:
Mathematical representation of gravitational force between two masses is given by universal law of gravity that states, “Every object in the universe attracts every other object with a force which is proportional to the product of their masses and inversely proportional to the square of the separation between them. The force acts along the line joining the centres of two objects.”
$F=G{\displaystyle \frac{Mm}{d^2}}$
Here G is a constant known as universal gravitation constant, M & m are the masses of the two objects separated by a distance d.
Gravity might also be carried by massless particles called gravitons.

Note:
 Gravity keeps all planets in our solar system in orbit around the sun by providing centripetal force.
Sometimes students confuse mass of the object and weight as the same thing. But these are different. The mass of an object is the measure of the object's inertial property while the weight of an object is the magnitude of the force exerted on the object by gravity.