Post a New Question

Physics

posted by .

A place kicker must kick a football from a point 37.1 m from a goal. As a result of the kick, the ball must clear the crossbar, which is 3.05 m high. When kicked the ball leaves the ground with a speed of 19.8 m/s at an angle of 53° to the horizontal.
(a) By how much does the ball clear or fall short of clearing the crossbar?
(b) Does the ball approach the crossbar while still rising or while falling?

  • Physics -

    Vo = 19.8m/s@53Deg.
    Xo = hor = 19.8cos53 = 11.92m/s.
    Yo = ver = 19.8sin53 = 15.81m/s.

    a. t = (Yf - Yo) / g,
    t(up) = (0 - 15.81) / -9.8 = 1.613s.

    d=Vo*t + 4.9*t^2 = 12.753 - 3.05=9.703m
    0 + 4.9t^2 = 9.703,
    t^2 = 1.98,
    t(dn) = 1.41s. to fall to 3.05m.

    Dh = Xo(t(up)+t(dn)),
    Dh = 11.92(1.41+1.613) = 36m=hor dist.

    Falls short by: 37.1 - 36 = 1.1m.

    b. While falling.

  • Physics -

    a. Falls short by 3 m

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

More Related Questions

Post a New Question