Acceleration Vector Word Problem

AI Thread Summary
The discussion revolves around calculating the average acceleration vector of a quarterback after being tackled, with initial and final velocities provided. The quarterback's initial speed is 4.6 m/s, and after impact, the combined speed is 3.8 m/s at an angle of +120° from his original direction. Participants emphasize the importance of correctly interpreting the angle and its impact on the velocity components, suggesting that one component may need to be negative. There is a request for a diagram to clarify the velocity components and ensure accurate calculations. The conversation highlights the need for clarity in the problem statement regarding the angle involved.
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Homework Statement


Famous quarterback Fleet O. Floote is attempting a quarterback draw by running up the middle toward his goal line at 4.6 m/s. A linebacker hits him squarely, and their combined final velocity is 3.8 m/s at an angle of +120.° from the quarterback's original direction. The time it took to change direction at impact was 0.20s. Choose an appropiate horizontal coordinate system and calculate the average acceleration vector of the quarterback during the tackle.

Homework Equations


a = ΔvΔt
329864.image3.png


The Attempt at a Solution


v1 = 4.6 m/s 90.0°
v2 = 3.7 m/s 120.°

v1x = 0 m/s
v1y = 4.6 m/s

v2x = 3.7 cos 60° = 1.9 m/s
v2y = 3.7 sin 60° = 3.2 m/s

I have this, but I feel that I'm missing something.
 
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Please draw a diagram, and show it to us. Thank you.

It seems to me, if the new velocity direction is 120 degrees to the original direction, one of the new components has to be negative.
 
Hello rf, :welcome:
Retweetfire said:
at an angle of +120.° from the quarterback's original direction
Can you post a sketch and compare with what you (were going to) calculate ? Then complete your attempt ?
 
BvU said:
Hello rf, :welcome:

Can you post a sketch and compare with what you (were going to) calculate ? Then complete your attempt ?
 

Attachments

  • IMG-20170319-WA0020.jpeg
    IMG-20170319-WA0020.jpeg
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That's only at a 30 degree angle to the QBs original velocity. Did they really mean 120 degrees, or did they really mean 30 degrees?
 
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