Projectile Motion

Most recent answer: 10/22/2007

Q:
what is the acceleration of a projectile thrown upward at it’s highest point?
- rabia (age 17)
bahawalpur/punjab/pakistan
A:
Well, assuming that we’re talking about a projectile thrown from the surface of the earth, then while the projectile is in flight the only acceleration it experiences is due to the force of gravity. (To be precise, there’s a little bit of other acceleration due to friction with the air, but that vanishes at the highest point of a straight up-down path because the velocity is zero there.) And the acceleration due to gravity is constant on the object thoughout its flight. So the acceleration of the projectile is equal to the acceleration due to gravity, 9.81 meters/second/second, from just after its thrown, through its highest point, and until just before it hits the ground.

If you search on the internet for ’projectile motion’ you will quickly find a ton of websites with little java appelets which demonstrate projectile motion. Many of these sites allow you to change certain variables, like the acceleration due to gravity, to see how they affect the projectile’s motion.

Hope this helps,

Tim

(published on 10/22/2007)