Tying an NFL Record

The physics of making a 63 yard field goal

By Alex Girden

™ http://www.youtube.com/watch?v=NfD25zFCxWg

What we Know

      Distance =63 yards

      1 yard=0.9144 meters

      Distance=58 meters

      Height of cross bar =10. feet

      1 foot=0.3048 meters

      Height =3.0 meters

      Football= 0.413 kg

      Estimated time of travel = 3 seconds

The easy idea

      Solving for initial velocity?

     Angle of kick?

     Kinetic Energy?

Calculations

      Δx=vot+1/2at^2

      3.o=vo (3 s)+ 0.5*-9.8* (3)^2

      Voy=16 m/s

      Max height- Vf^2=Vo^2+2aΔx

      Δx=13 meters

More equations

      Δx=vot+1/2at^2

      ax=0 m/s^2

      58=vo (3)

      Vox=19 m/s

      Vnet^2=vx^2 +vy^2

      Vnet=25 m/s

Unknowns

      sinΘ=16/25

      Θ=40 °

      Kinetic Energy given to ball

      KE=1/2mv^2

      ½ (0.413kg) (25)^2=129 J

Force of a kicker

      Time in contact with ball approximate=1.8 X 10^-3 s

      Vf=vo+at

      25=0 + a (1.3X 10^-3)

      Acceleration = 19,200 m/s

      Force=ma= (19,200 * 0.413 kg)=7,900 N

Future Directions

      Take into account wind speed and direction

      Air resistance’s affect on the ball