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victus00 [196]
3 years ago
6

A train travel on a straight track passing signal A at 20ms-1. It accelerates uniformly a 3ms-2 and reaches signal B 120m furthe

than A. At B, the velocity of the train is? ​
Physics
1 answer:
IgorLugansk [536]3 years ago
3 0

Since acceleration is uniform, if the velocity at point B is <em>v</em>, then

v^2 - \left(20\dfrac{\rm m}{\rm s}\right)^2 = 2\left(3\dfrac{\rm m}{\mathrm s^2}\right)(120\,\mathrm m)

Solve for <em>v</em> :

v^2 = \left(20\dfrac{\rm m}{\rm s}\right)^2 + 2\left(3\dfrac{\rm m}{\mathrm s^2}\right)(120\,\mathrm m) \\\\ v = \sqrt{\left(20\dfrac{\rm m}{\rm s}\right)^2 + 2\left(3\dfrac{\rm m}{\mathrm s^2}\right)(120\,\mathrm m)} \\\\ \boxed{v \approx 34 \dfrac{\rm m}{\rm s}}

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Explanation:

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Explanation:

Given:

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