Where did I go wrong for this projectile motion problem? (1 Viewer)

nuvardex

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Criteria uses Sx = (43.3)(5.1). Why? I thought that would only give you the range for one half of the parabola.
 

cossine

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Criteria uses Sx = (43.3)(5.1). Why? I thought that would only give you the range for one half of the parabola.
Your calculation for Uy is overly complicated. Uy = 50sin(30) = 25. The calculation other than that is correct it seems you plugged the wrong numbers in the calculator.

The working out seems set out in odd way. a = -9.8 has it is acting down not up. Your Vy seems to be the initial velocity in the y-direction but by convention it is just the velocity in the y-direction. So in other words you have swapped Vy and Uy.

So what you should really write is (Vy - Uy) / -9.8 = (Uy - Vy) /9.8.

I think your working out is perfectly good in that you will get the right answer but the working out can be improved. I am bit concern about the rounding that is done in the intermediate steps. Is it okay to round 50*cos(30) as 43.3? Since I have not studied Physics in highschool it would be good to hear your comment.
 

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