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Alkatran
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#17
Sep26-04, 08:08 PM
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Quote Quote by JohnDubYa
LURCH,
A rock is projected at 45 degrees at a initial speed of 10 m/s. If the rock was originally located at the bottom of a 30 degree incline, how far up (that is, along the incline) will it strike?

Now look over your cheat sheet and find an equation that solves this problem. :)
First make the problem a lot less ominous: Rotate everything 30 degrees. The mind works so much better with a level plane.

Then:
Calculate the new 'downward' force of gravity
Calculate the upward launch speed (with 15 degree launch angle, of course)
Get time via accel, speed change
Calculate sideways force of gravity
Calculate sideways launch speed
Get distance via time, accel, speed

QED, and I didn't use any 'weird' formulas except for a little rotation