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- Homework Statement
- Joe Varsity kicks a football of mass 0.9 kg. As his foot makes contact with the ball, it exerts a force which gradually increases to a maximum value over 5 milliseconds, then falls immediately to zero, as shown in the graph above. The force is given by the equation:

Force=(250 Newtons)∗(t/t0)^2

where t0 equals 1 millisecond.

What is the impulse given by Joe's foot to the ball? Don't forget the units

The ball was originally sitting on the tee, motionless. What is its speed immediately after Joe kicks it?

- Relevant Equations
- average force= impulse/(time)

**Homework Statement:**Joe Varsity kicks a football of mass 0.9 kg. As his foot makes contact with the ball, it exerts a force which gradually increases to a maximum value over 5 milliseconds, then falls immediately to zero, as shown in the graph above. The force is given by the equation:

Force=(250 Newtons)∗(t/t0)^2

where t0 equals 1 millisecond.

What is the impulse given by Joe's foot to the ball? Don't forget the units

The ball was originally sitting on the tee, motionless. What is its speed immediately after Joe kicks it?

**Homework Equations:**average force= impulse/(time)

Since impulse= (average force)*time

average force= (250 Newtons)∗(0.005s /1 milliseconds)^2= 6250N

impulse= (0.005 s)(6250N)= 31.25 J

Is J the right unit or is it N*s ?

momentum= (mass)(velocity)

momentum immediately after Joe kicks the ball= (250 Newtons)∗(0.001s /1 milliseconds)^2 * (0.001s) = 0.250N

0.250N = (0.9kg)(velocity)

velocity=0.278 m/s