SUVAT: Solving for t When s=(u+v)t/2

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To solve for time (t) using the equation s = (u + v)t/2, the correct rearrangement is t = 2s / (u + v). In the example of a car accelerating from 5 m/s to 20 m/s over 500 m, substituting the values gives t = 2 * 500 / (5 + 20), which simplifies to t = 40 seconds. To find acceleration (a), use the formula a = (v - u) / t, resulting in a = (20 - 5) / 40, which equals 0.375 m/s². The initial guess of 10 seconds was incorrect due to a miscalculation in the rearrangement.
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Using SUVAT if s=(u+v)t/2
would t=2s/(u+v)?
 
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Dan1601 said:
Hi, 1st day at college. 1st lesson on SUVAT and they set me a homework I am really struggling with hehe ended up coming here for ASAP for it being due tommorow.


I would say I am reasonably ok with it. One question I am just doubting I am right with is this:

A car accelerates uniformly from 5ms-1 to 20ms-1 over a distance of 500m.
How long does this take (t)
What is the cars acceleration? (a)


obviously using s=(u+v)t/2 but I am unsure how to rearrange it correctly. Taking a guess at 2s/(u+v)=t which provides me with an answer of 10. I don't think its correct because using t to find A i end up with 15/10 which doesn't sound correct. Please help

Your equation looks OK, but I can't see how you got 10 s out of it. Can you show what you did?
 
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