A football, if it was kicked when initially at rest, is inflated such that it will move in the direction of the kick with h=0.8 of the kicking foot's velocity
We now consider the same ball being kicked while it's moving towards the football player's foot. Before the kick the ball moves towards the soccer player with velocity v=10 m/s and the player kicks the ball in the opposite direction with foot velocity u=5 m/s.
What is the ball's speed after the kick in m/s?
12
no, it is wrong
To find the ball's speed after the kick, we need to use the principle of conservation of momentum. According to this principle, the total momentum before the kick is equal to the total momentum after the kick.
The momentum of an object is calculated by multiplying its mass by its velocity. Since the mass of the ball remains constant, we can ignore it in this calculation.
Before the kick:
The velocity of the ball towards the player is v = 10 m/s.
The velocity of the player's foot is u = 5 m/s.
After the kick:
Let's assume the speed of the ball after the kick is x m/s.
According to the principle of conservation of momentum, the total momentum before the kick is equal to the total momentum after the kick. The momentum before the kick is given by the sum of the momentum of the ball and the momentum of the player's foot. The momentum after the kick is simply the momentum of the ball.
Momentum before the kick = Momentum after the kick
(mass of the ball * velocity of the ball) + (mass of the foot * velocity of the foot) = (mass of the ball * velocity of the ball after the kick)
Since the mass of the ball remains constant, we can simplify the equation:
(mass of the ball * velocity of the ball) + (mass of the foot * velocity of the foot) = (mass of the ball * velocity of the ball after the kick)
Substituting the given values:
(10 m/s) + (-5 m/s) = x
Simplifying:
5 m/s = x
Therefore, the ball's speed after the kick is 5 m/s.