A football punter accelerates a .55 kg football

17.6 N

Explanation:

The force exerted by the punter on the football is equal to the rate of change of momentum of the football:

where

is the change in momentum of the football

is the time elapsed

The change in momentum can be written as

where

m = 0.55 kg is the mass of the football

u = 0 is the initial  velocity (the ball starts from rest)

v = 8.0 m/s is the final velocity

Combining the two equations and substituting the values, we  find the force exerted on the ball:

conduction, convection, radiation