Answer:
Explanation:
The velocity v₁ can be calculated with the kinematic formula:
Since the object is initially at rest, v₁ becomes:
Where g is the acceleration due to gravity. Now, the velocity v₂ can be calculated with the same formula, but now the initial velocity is v₁:
Substituting v₁ in this expression and solving for v₂, we get:
Now, dividing v₂ over v₁, we get the expression:
It means that v₂ is √2 times v₁.
by the concept of momentum conservation we can say
if net force on a system of mass is ZERO then its momentum will remain conserved
Here a ball is projected upwards so if we take Ball + Earth as a system then total momentum of the system will remain conserved
Initially when ball is on the surface of earth the system has zero momentum and hence we can say after throwing the ball momentum of earth + ball must be zero
now using same equation we can say
given that
from above equation velocity of earth will be
so above will be the recoil speed of earth