1. Apr 12, 2008

### TheKovac

1. The problem statement, all variables and given/known data
A object is projected with a velocity of 100 m/s at an elevations 30 degrees from a tower 150m high.

a) Time of flight
b) The horizontal distance from the tower at which the stone strikes that ground.
c) The magnitude and the direction of the velocity of the stone striking the ground.

2. Relevant equations
x=ut+0.5at^2
Trigonometry
v^2 = u^2 + 2ax
3. The attempt at a solution

a)

=>v=u+at
50.2=100 -10t
t1= 5.02s
t2 = 5.02s
t3=?

Am I on the right track at all?

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2. Apr 12, 2008

### gshyam

what are these t1 t2 and t3 ?
If you have the book PHYSICS by Resnic and Haliday please look in it for the solution.
bye

3. Apr 12, 2008

### Dr. Jekyll

You have some help here.

For the (a) part you have vertical shot (y component of the velocity) and then free fall from the height of 150 m at initial velocity of $$v_{y}=v_{0}sin\alpha.$$

For the (b) part you need the x component. You have the time from the (a) part, so it's pretty easy.

(c) part is also simple. You need the net velocity (trigonometry). X component doesn't change but the y component is increased by gravity.