Question

A stone is thrown upwards. Consider its upward and downward motion. In which case acceleration and when is retardation?

Answer 1

Answer:

For any body thrown near surface of earth the acceleration will be g downward. Hope this Helps! For this problem, assume that the acceleration of gravity is 10 m/s2 downward, and that all friction effects can be neglected.

Answer 2

Answer:

Let u be the initial velocity and h be the maximum height attained by the stone.

v

1

2

=u

2

−2gh,

(10)

2

=u

2

−2×10×

2

h

100=u

2

−10h ....(i)

Again at height h,

v

2

2

=u

2

−2gh

(0)

2

=u

2

−2×10×h

u

2

=20h ... (ii)

So, from Eqs. (i) and (ii) we have

100=10h

h=10m