How Fast Is a Football When It Passes 5 Meters High?

[physical?eer]

help! its driving me nuts!

a .565kg football is kicked from the ground at a speed of 22 m/s. what is its speed just as it passes between the uprights 5.0 m above the ground?

please help!

G:
m= .565 kg
v= 22m/s
5.0 m

r:
velocity

a:no kinematics's equations

 

[PhanthomJay]

Are you familiar with conservation of energy equations?

 

[m2003]

are needed to solve this problem, we can use the conservation of energy principle. The initial kinetic energy of the football is equal to its final potential energy as it passes between the uprights. We can set up an equation as follows:

Initial kinetic energy = Final potential energy

1/2 * m * v^2 = m * g * h

1/2 * .565 kg * (22 m/s)^2 = (.565 kg) * (9.8 m/s^2) * 5.0 m

Therefore, the velocity of the football just as it passes between the uprights is approximately 18.8 m/s. I hope this helps!