Results 1 to 2 of 2

Math Help - Physics - Projectiles

  1. #1
    Member
    Joined
    Oct 2008
    Posts
    135

    Physics - Projectiles

    Donovan McNabb passes a football at a velocity of 50 ft/s at an angle of 40 degrees to the horizontal toward an intended receiver 30 yd straight downfield. The pass is released 5 ft above the ground. Assume that the receiver is stationary, is isolated and that he can catch the ball from the ground (a shoestring catch) up to a height of 7 ft when the ball arrives at his position. Will the pass be completed? If not will it be short or long? If the conditions (launch height, distance to receiver, height for catch) are exactly the same but the quarterback can launch the football at 45 degrees to the horizontal what is the range of speeds he must give the ball at launch so as to make a completion?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by ajj86 View Post
    Donovan McNabb passes a football – at a velocity of 50 ft/s at an angle of 40 degrees to the horizontal – toward an intended receiver 30 yd straight downfield. The pass is released 5 ft above the ground. Assume that the receiver is stationary, is isolated and that he can catch the ball from the ground (a shoestring catch) up to a height of 7 ft when the ball arrives at his position. Will the pass be completed? If not will it be short or long? If the conditions (launch height, distance to receiver, height for catch) are exactly the same but the quarterback can launch the football at 45 degrees to the horizontal what is the range of speeds he must give the ball at launch so as to make a completion?
    Here's a start:

    Consider the motion of the football in the vertical and horizontal directions:

    Horizontal direction:

    u = 50 cos(40) m/s
    a = 0 m/s^2
    x = 30 m
    t = ?

    Calculate t using an appropriate formula.

    Vertical direction:

    u = 50 sin(40) m/s
    a = -9.8 m/s^2
    t = get from above calculation.
    y = ?

    Calculate y using an appropriate formula.

    If y > 2 (yes y > 2, NOT 7. Why ....?) or y < -5 (yes, y < -5 because then the football falls short. Why ....?) the football cannot be caught.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Projectiles
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: November 21st 2010, 08:13 AM
  2. Projectiles
    Posted in the Math Topics Forum
    Replies: 4
    Last Post: June 23rd 2010, 07:47 AM
  3. Projectiles
    Posted in the Math Topics Forum
    Replies: 2
    Last Post: January 8th 2010, 03:46 AM
  4. projectiles?
    Posted in the Calculus Forum
    Replies: 2
    Last Post: May 16th 2009, 10:15 AM
  5. Projectiles again
    Posted in the Calculus Forum
    Replies: 3
    Last Post: May 4th 2009, 09:23 AM

Search Tags


/mathhelpforum @mathhelpforum