Question

a stone of mass 10 kg is dropped from a height 10 metre what will be its velocity at a height of 2 metre from the ground​

Answer 1

Answer:

Given that,

Mass of the stone = 10 kg

The height = 10 m

We need to find the : The velocity of the stone at a height of 2 m from the ground.

The initial velocity of the stone is obviously 0 m/s because initially the stone is at rest.

We need to find the velocity at the height 2 m above ground, hence, the distance travelled by the stone before reaching 2 m above the ground = 10 - 2 = 8 m.

We know, The acceleration due to gravity = 9.8 m/s².

The third equation of motion : v² - u² = 2as.

⇒ v² - 0² = 2*9.8*8

⇒ v² = 156.8

⇒ v = √156.8

⇒ v = 12.5 m/s

Hence, the velocity of the stone at a height of 2 m above the ground = 12.5 m/s.

THREE EQUATIONS OF MOTION -

• v = u + at
• s = ut + ½at²
• v² - u² = 2as

Answer 2

Answer:

distance= 10 meter

2 meter above ground means 10 - 2 = 8m

so

v^2-u^2=2as

u = 0 a= 9.8 m/s^2 gravitational acceleration

v^2 - 0^2 = 2×9.8×8

v^2= 156.8

v=√156.8

v = 12.52 m/s