Projectile Motion
Pronunciation: /prəˈdʒɛk taɪl ˈmoʊ ʃən/ ?
Projectile motion is the vertical motion of an object
in a gravitational field given an initial
velocity
and
height.
The
quadratic equation
for projectile motion is:
where
t represents time,
a represents
acceleration
due to gravity,
v_{0} represents the initial
velocity,
and
h_{0} represents initial
height.
Since down is taken to be negative, acceleration due to gravity is a negative number.
Manipulative
 Manipulative 1: Projectile motion. Created with GeoGebra. 

Click on the points on the blue sliders in manipulative 1 and drag them to change the figure.

Example
 Jeff is standing on top of 20 foot tower. He throws a stick down
at an initial velocity of 10 ft/s. Use 32 ft/s^{2}
for the acceleration due to gravity. What is the equation for the vertical height
of the stick? At what time does the stick reach the ground?
Step  Equation(s)  Description 
1   Identify the values of the constants. 
2   Plug the constants into the equation. Simplify the equation. 
3   Set the height to zero. 
4   Apply the quadratic formula. 
5   Since a negative solution does not make sense in this problem, the negative solution is extraneous solution. Discard the extraneous solution. 
Example 1 
Cite this article as:
Projectile Motion. 20090110. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/p/projectilemotion.html.
Translations
Image Credits
Revision History
20090110: Initial version (
McAdams, David.)