1
discovered the phenomenon of growtation
2 A force that acts on an object moving abog a circle
and which is directed towards the centre of the
Chicle is called
force
3 ous that describe plondary motion og by
is the curve obtained thas a core is
cut by ao inclined plane
The cale of mass of a special object honeg
tarifa density is at its -----
6. The conse of any object having wiform dorady
Answers
Answer:
Explanation:
We have learnt about the motion of objects and force as the cause of motion in the previous chapters. We have learnt that a force is needed to change the speed or the direction of motion of an object. We always observe that an object dropped from a height falls towards the earth. We know that all the planets go around the Sun. The moon goes around the earth. In all these cases, there must be some force acting on the objects, the planets and on the moon. Isaac Newton could grasp that the same force is responsible for all these. This force is called the gravitational force.
In this chapter we shall learn about gravitation and the universal law of gravitation. We shall discuss the motion of objects under the influence of gravitational force on the earth. We shall study how the weight of a body varies from place to place. We shall also discuss the conditions for objects to float in liquids.
We know that the moon goes around the earth. An object when thrown upwards, reaches a certain height and then falls downwards. It is said that when Newton was sitting under a tree, an apple fell on him. The fall of the apple made Newton start thinking. He thought that: if the earth can attract an apple, can it not attract the moon? Is the force the same in both cases? He conjectured that the same type of force is responsible in both t he cases. He argued that at each point of its orbit, the moon falls towards the earth, instead of going off in a straight line. So, it must be attracted by the earth. But we do not really see the moon falling towards the earth