Question

@ A stone falls from 90 m height it is total
PE converts in to KE calculate the velocity
with which the stone strike on the ground.
Soin.​

Answer 1

Answer:

The split second that we first let go of the stone, it’ll have no speed at all. So its initial speed, let’s call it u, is zero, i.e. u = 0 m/s.

As the stone is falling, it’ll speed up due to gravity. Let's call that acceleration g. On the Earth’s surface (i.e. at sea level) and even 90 m above it, it'll be roughly true that the free falling stone will speed up by 9.81 m/s each second. (You can look up this value online.) In short, its acceleration is roughly a steady, unchanging:

g = 9.81 m/s every second.

In other words, after 1 second, the stone’s final speed, v, would be v =(9.81 × 1) m/s.

After 2 seconds, the stone’s speed would be v = (9.81 × 2) m/s.

After 3 seconds, the stone’s speed would be v = (9.81 × 3) m/s.

In general, after t seconds, the stone’s speed would be v = 9.81 × t = gt.