(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The motion of a human body through space can be precisely modeled as the motion of a particle at the body's center of mass. The components of the displacement of an athlete's center of mass from the beginning to the end of a certain jump are described by the two equations below, where t is the time at which the athlete lands after taking off at time t = 0.

xf =0 + (11.1 m/s)(cos 20.3°)t

0.369 m = 0.812 m + (11.1 m/s)(sin 20.3°)t - 1/2(9.80 m/s2)t2

2. Relevant equations

(a) Identify his position.

? meters ihat + ? meters jhat

(b) Identify his vector velocity at the takeoff point.

? m/s at ? ° above horizontal

(c) The world long jump record is 8.95 m. How far did the athlete in this problem jump?

? m

3. The attempt at a solution

So, I drew out a diagram and it seemed to make sense to me but the answers were wrong. for a) i got you would just take the component vectors, so Vxi= (11.1 m/s)(cos 20.3) and Vyi= (11.1 m/s) (sin20.3). But that was wrong. I got b). and for c) i thot you could jus pick out the information and it would be .369 but then realized that is only in the y direction, but time isnt give, so how are we supposed to find the x_final?

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# Homework Help: Projectile Motion given 2 position equation

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