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Complex Projectile Motion question. Algebra help needed 
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#1
Nov810, 06:43 PM

P: 6

1. The problem statement, all variables and given/known data
A cow, with a mass of 327 kg, if fired from a medieval catapault, and travels a horizontal distance of 1375 m. It lands in a depression 39 m below its starting position. If it is launched at an angle of 37.0above the horizontal, find its initial speed. Givens HOR dx= 1375 V1x= ? ax= 0m/s2 v2x=v1x VER dy= 39 m v1y= ? ay= 9.81m/s2 v2y=? T=? 2. Relevant equations [tex] x = x_0 + v_0 t + (1/2) a t^2 [/tex] 3. The attempt at a solution What I did here was make a equation for time of flight for the horizontal dx=v1*cos37* t +1/2 at^2 1375=v1x*cos37*t t= 1372/v1*cos37 I then entered this into my vertical distance dy=v1y*cos37* t +1/2 at^2 39=v1*sin37*(1372/v1*cos37) + 1/2 (9.81)(1372/v1*cos37)^2 Now this equation is where it gets tricky, I am not sure how to solve for v1. 


#2
Nov810, 07:40 PM

P: 13

at that point you should plug in to get rid of sin and cos so you are working with decimals and just follow order of operations. if you have a graphing calculator it would make life much easier but if not just plug and chug and go step by step as to not lose anything.



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