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The discussion focuses on correcting a calculation related to velocity after an initial acceleration period. The correct formula for velocity is applied, revealing that the final speed should be 44 m/s instead of 64 m/s due to a miscalculation that double-counted the initial speed. This error impacts the subsequent calculations for stopping time, distance, and the overall graph representation. As a result, the answers provided for the related questions are deemed incorrect. Accurate calculations are crucial for ensuring the validity of the entire analysis.
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Homework Statement
I've completed it but I don't think it's right could someone please check?
Relevant Equations
Equations of motion
See question and attempt answer below. Thanks.
 

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i), ii) and iii) I agree with your answers.

However check your calculation for the velocity after the initial 2 min acceleration...

V=U+at
U=20 m/s
a=0.2 m/s/s
t=120 s (2min)

= 20 + (0.2*120)
= 20 + 24
= 44m/s

eg not 64m/s

I think you double counted the initial 20m/s.

That effects the stopping time and distance and the time at constant velocity.
 
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As explained above, answer iv) and graph are not correct because the calculated value of speed for end of acceleration period/beginning of slope is too high.
For same reason, calculated times values are not correct.
 
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