The work of Issac newton is he discovered the gravity.
when he was sitting the the shed of the tree than an apple suddenly fall in his head but he did not realize and again the apple hit the Issac newton head. so there is a saying that there is an apple in Newton head. after that he pick the same apple and thrown into the tree than the apple goes up than again it came down than he think that an object thrown up how it again comes down than later on by many experiment and research he find that it is due to gravity. so this Way he discovered gravity.
