winterWx

posted by .

A soccer player kicks a soccer ball of mass 0.45 kg that is initially at rest. The force of the kick is given by F(t) = [(5×106)t - (2.5×109)t2] N for 0 ≤ t ≤ 2.0×10-3 s, where t is in seconds. (The player's foot is in contact with the ball for 2.0×10-3 s.) Find the magnitude of the impulse on the ball due to the kick. Find the average force on the ball from the player's foot during the period of contact. Find the maximum force on the ball from the player's foot during the period of contact. Find the ball's velocity immediately after it loses contact with the player's foot.

Integrate the force vs time function during the period of contact. This will tell you the momentum delivered to the ball.

Impulse = Integral of a t- b t^2
from t = 0 to t = 2*10^-3 s,
where
a = 5*10^6 and b = 2.5*10^9
The integral is at^2/2 - bt^3/3.
Evaluate it at the limits of integration and take the difference.
The average force is the impulse divided by the time of contact.
The maximum force occurs when f'(t) is zero, which is when
a = 2 b t
t = a/(2 b) = 1.0*10^-3 s.
The ball's velocity when it leaves the foot = (momentum change)/mass = (impulse)/mass
(since the initial momentum is zero)

Great...I got it. Thanks :)

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. physics

    A soccer ball with mass 0.410 kg is initially moving with speed 4.30 m/s. A soccer player kicks the ball, exerting a constant force of magnitude 44.0 N in the same direction as the ball's motion. Over what distance must the player's …
  2. Physics

    A soccer player kicks a ball into the air at an angle of 36 degrees above the horizontal with a speed of 30m/s a.How long is the soccer ball in the air?
  3. Physics

    A soccer player kicks a ball into the air at an angle of 36.0 Degrees above the horizontal. The initial velocity of the ball is +30.0 m/s. 1).How long is the soccer ball in the air 2).What is the horizontal distance traveled by the …
  4. physical science

    A soccer player applies a force of 51.5 N to a soccer ball while kicking it. If the ball has a mass of 0.46 kg, what is the acceleration of the soccer ball?
  5. physics

    A 0.405 soccer ball is initially moving at 2.05. A soccer player kicks the ball, exerting a constant 40.5 force in the same direction as the ball's motion.
  6. physics

    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 …
  7. physics

    A 0.5 kg soccer ball is kicked with a force of 50 Newtons for 0.2 sec. The ball was at rest before the kick. What is the speed of the soccer ball after the kick?
  8. Physics help

    A soccer player kicks a soccer ball at +10.0 m/s at an angle of 60°. What are the horizontal and vertical components of velocity of the kick?
  9. science

    A soccer player applies an average force of 180 N during a kick. The kick accelerates a 0.45 kg soccer ball from rest to a speed of 18 m/s. What is the impulse imparted to the ball?
  10. Physics

    A soccer ball of mass 550g is at rest on the ground. The soccer ball is kicked with a force of 108N. The player shoes is in contact with the ball for 0.3m. What is KE of the ball?

More Similar Questions