Question

Please help me, I am in dire need of it,
A football quarterback shows off his skill by throwing a pass {5.70 m downfield and into a bucket. The quarterback consis- tently launches the ball at 38.00' above horizontal, and the bucket is placed at the same level from which the ball is thrown. What initial speed is needed so that the ball lands in the bucket? By how much would the launch speed have to be increased if the bucket is moved to 46.50 m downfield? So I did 5.7cos(38)= 4.49, 2sin(38)/9.8= 0.12 1.23 and 46.50 cos(38)=36.64 did I do this correctly and what shall I do next?

Answer 1

horizontal motion:
46.50=Vi*cos38*time
verticalmotion
hf=hi+vi*sin38*t-1/2 9.8 t^2 hf=hi=0
so have two equations, two unknowns (time t, and vi)
solve for time t in the first eequation, put that into the second equation and solve for vi
a bit of algebra is required.

Answer 2

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