Find the time taken by the truck to move 1 metre

AI Thread Summary
The discussion centers on a perceived error in a textbook regarding the time taken by a truck to move 1 meter. The correct formula for calculating time, given initial velocity is zero, should be t = √(2s/a), leading to a result of 5 seconds. The original suggestion of t = √(s/a) is challenged as incorrect. Participants emphasize the importance of using the correct kinematic equations for accurate calculations. The conversation highlights the need for clarity in physics problem-solving.
chwala
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Homework Statement
See attached.
Relevant Equations
kinematics
Unless i am missing something; there is an error with the textbook

1707127143855.png


It ought to be ,

## t= \sqrt {\dfrac{1}{0.04}}= \sqrt 25 = 5## seconds.
 
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Why ?
 
chwala said:
Homework Statement: See attached.
Relevant Equations: kinematics

Unless i am missing something; there is an error with the textbook

View attachment 339804

It ought to be ,

## t= \sqrt {\dfrac{1}{0.04}}= \sqrt 25 = 5## seconds.


If u = 0 then s = \tfrac12 at^2 \quad \Rightarrow \quad t = \sqrt{\frac{2s}{a}} as the textbook has, not t = \sqrt{s/a} as you are suggesting.
 
pasmith said:
If u = 0 then s = \tfrac12 at^2 \quad \Rightarrow \quad t = \sqrt{\frac{2s}{a}} as the textbook has, not t = \sqrt{s/a} as you are suggesting.
Let me take a break! Cheers @pasmith
 
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