Okey, my exam is in four days and im officially freaking out! I seem to have forgotten everything having been revising for other exams...urg...can't even do basic mechanics questions!
So any help would be greatly, greatly appreciated!
Stone is thrown Horizontally with speed 15m/s from top of a cliff, 30 meters high. Estimate the distance of the stone from the thrower when it is level with the foot of the cliff and the time it takes for the stone to fall.
Now, wth? With the given information all we have is U = 15m/s...how is it possible to find S?
Thanks!
Motion in the vertical direction (take downwards as the +ve direction):
a = 9.8 m/s^2
s = 30 m
u = 0 m/s
t = ?
Find t using .
Motion in the horizontal direction:
a = 0 m/s^2
u = 15 m/s
t = value calculated above.
s = ?
Find s using . This is the distance from the base of the cliff, which is not the same as the distance of the stone from the thrower.
If you want the distance of the stone from the thrower, then you need to use Pythagoras' Theorem: where d is the distance and s is the value calculated above.