A football reciever B runs the slant in pattern, making a cut at P and thereafter running with a constant speed [tex]v_B=21ft/sec[/tex] at an angle of 30 degrees from the y-axis. The quarterback releases the ball with a Horizontal velocity [tex]v_A_x=100ft/sec[/tex] the instant the reciever passes pont P. Determine the angle at [tex]\alpha[/tex] (the angle between Va and the x-axis) and determine the velocity of the ball relative to the reciever when the ball is caught. Neglect any vertical motion of the ball.(adsbygoogle = window.adsbygoogle || []).push({});

The answer is given [tex]\alpha=33.3[/tex] degrees and [tex]v_A_/_B= (73.1 i + 73.1 j)ft/sec[/tex]

I tried to solve this by finding the time both the football and the reciever reach the same distance by using [tex]100*t = 21*sin(30)*t+45[/tex]

I used this time to find the displacement of the reciever from (45,45)... then I tried to use [tex]tan(\frac{s_y}{s_x})=\alpha[/tex]. (the[tex]s_y[/tex] and [tex]s_x[/tex] I used were [tex]s_y=35.85[/tex] and [tex]s_x=50.28[/tex]But the alpha I get is 35.488 degrees, which is quite a bit higher. I was wondering what I am doing wrong.

Thanks in advance

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# Homework Help: Relative Motion of a football player

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