(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A projectile is to be launched so as to go from A to B [which are respectively at the bases of a double inclined plane having angles [itex]\alpha[/itex] and [itex]\beta[/itex] as seen in the figure] and just barely miss a pole of height [itex]H[/itex] that is located at the tip. If the distance between A and B is D, find the angle with the horizontal at which the projectile should be launched.

[PLAIN]http://b1111.hizliresim.com/r/k/llf5.jpg [Broken]

3. The attempt at a solution

[PLAIN]http://b1111.hizliresim.com/r/k/llds.jpg [Broken]

I found [itex]h=\frac{D\tan\alpha\tan\beta}{\tan\alpha+\tan\beta}[/itex]

and I considered a particle which is at B is falling free.And Vo vector aimed to point B when t=0 , so they must collide at [itex]t=t_{collide}[/itex] and at top of the H.

Then i wrote [itex]\tan\phi=\frac{1/2gt_{collide}^2+H+h}{\frac{D\tan\beta}{\tan\alpha+\tan\beta}}[/itex]

and i found

[itex]\phi= \tan^-1(\frac{(1/2gt_{collide}^2+H)(\tan\alpha+\tan\beta)+D\tan \alpha \tan\beta}{D\tan\beta})[/itex]

Is my answer is correct ? and are there any solutions for conditions which are before reaching maximum height and minumum height ?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Projectile Motion Problem. Is my answer correct ?

**Physics Forums | Science Articles, Homework Help, Discussion**