Re: projectile motion:
Physics Campfire
If ye would like to moderate the Physics
Campfire, please drop becket@jollyroger.com a
line.
[Open Source CMS
Renaissance][Postnuke Hosting][Gallery
Hosting][Blog Hosting]
DR. ELLIOT'S NORTH AMERICAN GREAT BOOKS TOUR--COMING TO A BOOK
STORE NEAR YOU
[GREAT
BOOKS: DISCUSS THE
TRAGEDY OF DRAKERAFT.COM][Great Books Lovers Match]
[Physics Forums][Poetry][Shakespeare's Plays][Great Books][Open Source Business]
[Great Books Games][Federalist Papers][Poetry Contest][Classic eCards][Great Books
Forums]
The new Physics Forum is at
http://killdevilhill.com/physicschat/wwwboard.html and
jollyrogerwest.com.Due to spam and off-topic content, these forums are being phased out and replaced with new
great books forums. Please join us!
The
World's Largest Literary Cafe
[Jollyroger.com][Carolinanavy.com][Nantuckets.com][BusinessPhilosophy.com][Classicals.com][Quarterdeck][xmlclics.com]
[
Jolly Roger Live
Chat][The Jolly Roger][Kill Devil
Hill][Western Canon University]
[Federalistnavy.com][Starbuck.com][Linux Poetry]
[ussconstitutions.com]
[Free jollyrogermail][William
Shakespeare]
[JR Greetings]
[nantucketnavy.com][hatteraslight.com][Clicgreetings.com]
[MASTHEAD SEARCHTM]
[ Follow Ups ] [
Post Followup ] [ Physics Campfire ] [ ]
[The
World's Largest Literary Cafe]
Posted by David on April 23, 19101 at 12:48:16:
In Reply to: projectile motion posted by Luke on April 23, 19101 at 07:20:08:
You don't need to worry about unit vectors as it has been complicated by the Hawking forum fool who can't even decide what a uniform g field means. I'll demonstrate how to get the range-angle equation and you can work it from there. You have
x = (v0cosq)t
y = (v0sinq)t - (1/2)gt2
It lands at y = 0 and so you have
0 = (v0sinq)t - (1/2)gt2
0 = t[v0sinq - (1/2)gt]
If it started at t = 0 then the other solution is
t = (2/g)v0sinq
Using this in the first equation at the top of the page results in
x = (v0cosq)(2/g)v0sinq
which with a trig identity simplifies to
x = (v02/g)sin(2q)
This equation will result in two angles for a given range and velocity except for the particular combination that gives you q = p /4.
Follow Ups:
Post a Followup