A boy kicked a football with an initial vertical velocity component of 15.0 m/s
and a horizontal velocity component of 22.0 m/s.
a) What is the velocity of the football (magnitude and direction)?
The velocity can be represented by this triangle:
* | 15
* θ |
* - - - - - - - *
The magnitude of the velocity is the length of the hyptenuse.
. . m/s.
The direction of the velocity is given by:
b) How much time is needed to reach the maximum height?
The height of the football is given by: .
The graph is a down-opening parabola which reaches its maximum at its vertex.
The vertex is at: .
The ball reaches maximum height in abut 1.5 seconds.