+0  
 
0
221
1
avatar

Sanjay attempts a 49-yard field goal in a football game. For his attempt to be a success, the football needs to pass through the uprights and over the crossbar that is 10 feet above the ground. Sanjay kicks the ball from the ground with an initial velocity of 73 feet per second, at an angle of 34° with the horizontal. What is true of Sanjay's attempt?

 

  • The kick is not successful. The ball is approximately 2 feet too low.
  • The kick is good! The football clears the crossbar by approximately 5 feet.
  • The kick is not successful. The ball is approximately 5 feet too low.
  • The kick is not successful. The ball is approximately 8 feet too low.
 May 9, 2020
 #1
avatar+28021 
+1

x component of trajectory =   73 cos 34   f/s   

    Now how long will it take to travel 49 yards (= 147 feet) ?

          147 / (73 cos 34) = 2.43 seconds

 

INITIAL y component of trajectory = 73 sin 34 f/s = 40.82 f/s  

     but THIS velocity is acted upon by gravity

        y = y0 + vot - 1/2 a t^2       

                          y0 = 0        Now we need to know the y value at 2.43 seconds to see if it will clear the uprights

 

        y = 40.82 (2.43)  - 1/2 (32.174)(2.43)= 4.2 Feet      Tooo low !   Missed it by  5.8 feet

 May 9, 2020
edited by ElectricPavlov  May 9, 2020

29 Online Users

avatar
avatar