Projectile Problems

[Velociraptor42]

Has anyone gotten anywhere on problem 2 (a or b since one leads to the other)? I've made like five tables and I feel like if I could just figure out the first step I could get the rest of it to fall together... 

Even Cricket got bored watching me sit there trying it for a half hour

[Velociraptor42]

Actually, I think I got it now, so never mind ^.^

[walsh416]

break it up into x components and y components.  You know that Vox and Vfx are equal and Ax is zero, and that Ty equals Tx (times are the same..duh).  You also know that Vox=Voy because the angle is 45deg.  Do some kinemagic equation stuff and find x=.5(Vo+Vf)T, which becomes 618=Vx(T) for the x component and y=VoyT+.5aT^2, which becomes -3=Vx(T)-16T^2 for the y components.  (Vx is interchangeable for Vox, Vfx, and Voy because they're all the same.  Doe some systems magic and you'll get your answer (140.287 f/s, I hope).

[walsh416]

The other two build on that concept, except instead of Vox = Voy straight up, you need to get triggy with them.

[Velociraptor42]

Get triggy with 'em...XD

That is what I got so phew! I feel a lot better now that I know someone else got the same answer as me.

[bazinga818]

Where did your .5 go when you substituted x=.5(Vo+Vf)*T to get 618=VxT?

[bazinga818]

Nevermind got it haha it's too late I can't do proper math

[FizziksGuy]

Your cat is named Cricket?  I have a dog named Cricket:

 

 

And she is very cat-like.