Question

why do we neglect gravitational force exerted on a falling stone by near by tree while calculating its acceleration

Answer 1

All the objects in the universe attract each other with Gravitational force ( $F = \frac{Gm_{1} m_{2} }{r^2}$) . The acceleration due to this force on a body( here, stone) is directly proportional to the mass of the other body (here tree and earth).
When you suspend a stone freely, it will fall downwards due to gravitational force exerted by the earth. Although, the tree will also attract the stone towards it with some gravitational force, but that force is too minimal as compared to earth's gravitational force. 
order of mass of the earth: $10^{24}$ Kg
order of mass of the stone: 1 Kg

Answer 2

Answer:

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