Posted by Anonymous on .
a stone propelled from a catapult with a speed of 50m/s attains a height of 100m calculate the angle of projection

9th grade physics needs help 
PsyDAG,
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9th grade 
Damon,
What is its initial vertical speed Vo ?
v = Vo  9.8 t
v = 0 at top
so
t = Vo/9.8
then height
h = Vo t  (9.8/2) t^2
100 = Vo^2/9.8  (9.8/2) (Vo/9.8)^2
100 = Vo^2/(2*9.8)
Vo = 44.3 = speed sin theta
sin theta = 44.3/50
theta = 62.4 deg up from horizontal  physics  Uwagboe,