Tricky Dynamics Kinematics Trajectory Problem

  • #1

Homework Statement



A football player attempts a 29-yd field goal. If he is able to impart a velocity u of 95 ft/sec to the ball, compute the minimum angle θ for which the ball will clear the crossbar of the goal. The crossbar is 10 ft above the ground. (Hint: Let m = tan θ.)


Homework Equations

I can't find and equation for minimum angle anywhere, which makes me think I have to combine two equations to be able to solve this. I've messed with equations on here, http://hyperphysics.phy-astr.gsu.edu/hbase/traj.html#tracon for hours and I can't figure out what equations I need to combine to get a minimum angle.



The Attempt at a Solution



I know my range is 87 feet, and the height that i want to clear is 10 feet at the end of my range, kicking the field goal at the smallest initial angle possible. Velocity is 95 ft/s

Any help on this is appreciated, it may simply be one of those problems where the solution seems too easy so it is overlooked?
 

Answers and Replies

  • #2
1,137
0
well draw figure and you'll understand that range is not 29 yd
question says that when x= 29 yd ... y should be 10 ft
 
  • #3
verty
Homework Helper
2,164
198
I've had a look at this question, it was by no means easy. Here's a hint: the formula for the height of the ball versus time must have real roots.
 

Related Threads on Tricky Dynamics Kinematics Trajectory Problem

  • Last Post
Replies
4
Views
880
  • Last Post
Replies
0
Views
2K
Replies
14
Views
943
  • Last Post
Replies
7
Views
688
  • Last Post
Replies
3
Views
1K
  • Last Post
2
Replies
35
Views
3K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
3
Views
2K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
1
Views
2K
Top