A body is thrown upwrd then return to same level,has there been any change inits acceeration at instant motion

Answer 1

No.the acceleration of an object which is throwned upward(or it can have a free fall,or a fall with an initial speed)never changes,and it is always g=10m/s^2.

Answer 2

As you go away from the earth you are climbing at different time levels and gravity energy level.
The acceleration changes it is not constant as is erroneously believed.
The formula for acceleration is= Gravity Energy per unit distance divided by the value of the mass of the upward moving body.
This equates as follows;
acceleration due to gravity = G * M/ R^2
Where G is Newton constant
M is the larger gravitational mass= earth in this case.
R is the distance beween the upward moving body and the distance to the center of the Earth.
As per above acceleration due to gravity is variable.
When the Body comes down again to the same location on the earth's surface ,the acceleration would be the same value as when he initially started. Of couse he will experience a gravity force called weight.

Answer 3

Technically, the acceleration is a tiny bit smaller as you go up, but for all practical purposes the acceleration is the same for the whole time of flight.

If you were to throw something upwards at 30 m/s (about 60 MPH), roughly speaking the speed would go like (using 10 m/s/s as g).

0 s->30 m/s
1 s->20 m/s
2 s->10 m/s
3 s->0 m/s
4 s->-10 m/s
5 s->-20 m/s
6 s->-30 m/s

The whole trip, the ball loses 10 m/s every second.

Technically speaking, this isn't the speed, but the vertical component of the velocity, but we don't need to worry about that detail right now.

Answer 4

If we ignore the friction, no. the body will have the same acceleration (only sign of velocity is reversed), which is the acceleration due to gravity. The velocity will be the same at that point, but as mentioned, with the sign reversed.