A 0.42 kg soccer ball is moving down field with a velocity of 12 m/s. A player kicks the ball so that it has a final velocity of 18 m/s down field. What is the change in the balls momentum? and find the constant force exerted by the players foot on the ball if the two are in contact for 0.020 s?

Respuesta :

Answer:

the change in momentum is 2.52 N·s

the constant force on the ball while in contact with the players foot is 126 N

Explanation:

p=momentum

m=mass

v=change in velocity

p=(0.42)(6)

p=2.52

The change in the ball's momentum is 2.52 kgms⁻¹

The constant force exerted by the players foot on the ball is 126 N

From the question,

We are to determine the change in momentum of the ball

Change in momentum calculated by using the formula,

[tex]\rho = m(v-u)[/tex]

Where [tex]\rho[/tex] is the change in momentum

[tex]m[/tex] is the mass

[tex]v[/tex] is the final velocity

and [tex]u[/tex] is the initial velocity

From the given information,

[tex]m = 0.42 \ kg[/tex]

[tex]u = 12 \ m/s[/tex]

[tex]v = 18 \ m/s[/tex]

Therefore,

Change in the ball's momentum,

[tex]\rho = 0.42 (18-12)[/tex]

[tex]\rho = 0.42 (6)[/tex]

[tex]\rho = 2.52 \ kgms^{-1}[/tex]

Hence, the change in the ball's momentum is 2.52 kgms⁻¹

For the force exerted by the players foot

Force is given by change in momentum with time

That is,

[tex]F = \frac{\rho}{t}[/tex]

Where

[tex]F[/tex] is the force

[tex]\rho[/tex] is the change in momentum

and [tex]t[/tex] is the time

From the given information

[tex]t = 0.020 \ s[/tex]

Therefore,

[tex]F = \frac{2.52}{0.020}[/tex]

[tex]F = 126 \ N[/tex]

Hence, the constant force exerted by the players foot on the ball is 126 N

Learn more on calculating change in momentum here: https://brainly.com/question/12144602