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Here is the question, it is very simple.
A toy car accelerates by means of a rocket-type engine for 20 m. If the acceleration during the burn is [tex]5 m/s^2[/tex] and the burn lasts for 3 s, determine the velocity of the car at the end of the burn.
It seems like the obvious one, and we use.
[tex]v=v_i + at[/tex]
...and we get 15. This works for uniform acceleration, which it says it is.
They are using...
[tex]s = v_f t - 1/2 a t^2[/tex]
They got that by differentiating from [tex]v_i[/tex], instead of the usual [tex]v_f[/tex]
In the end, they get 14.2 m/s.
A toy car accelerates by means of a rocket-type engine for 20 m. If the acceleration during the burn is [tex]5 m/s^2[/tex] and the burn lasts for 3 s, determine the velocity of the car at the end of the burn.
It seems like the obvious one, and we use.
[tex]v=v_i + at[/tex]
...and we get 15. This works for uniform acceleration, which it says it is.
They are using...
[tex]s = v_f t - 1/2 a t^2[/tex]
They got that by differentiating from [tex]v_i[/tex], instead of the usual [tex]v_f[/tex]
In the end, they get 14.2 m/s.
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