When a ball is throwm upwards .Its momentum first decreases and then increasee . Its conservation of linear momentum violated in this process. Answer?
Answers
F = dP/dt where P is linear momentum and F is external force.
Now, if F = 0 then dP/dt = 0 which leads to the result that dP = 0, on integrating both sides we get, P = constant which means it is conserved.
But when there is external force applying on body, then its momentum can't be constant anymore.
Here in this case of throwing ball upwards, the ball is in action of many external forces like weight, air drag, etc which leads to change the momentum of the ball with time.
Hence, law of conversation of momentum is holds only when no external force acting on the body.
Answer:
NO, law of conservation of momentum not violated in this process.
The combined momentum of a ball and the earth is conserved. The ball attracts the earth by the same force as the earth attracts the ball. When the ball upward, its Momentum decrease in the upward direction but simultaneously the momentum of the earth increases in the upward direction at the same rate. Similarly, when the ball falls down, its Momentum increase in the downward direction but simultaneously the momentum of earth increases in upward direction at the same rate.