(adsbygoogle = window.adsbygoogle || []).push({}); Motion Equation Help, Please :)

Hi, could anyone help me out with the following? My teacher gave us homework without explaining it :'(. I've tried to work out the answers, but I don't know if they're right.

So, could someone work them out for me, please?

This question is about a sprinter running a 100m race.

(a) A sprinter accelerates uniformly to a maximum speed over the first 30m of a race in a time of 5.0s. Calculate his acceleration.

(I've tried this one, but my answer isn't a very logical one.) I got 6 m.s-2 for this one. Don't know if it's right though.

(b) Calculate his maximum velocity.

(I can't do this one, at all. I don't even know how to calculate velocity. Could someone please explain how to do this? Thanks, could you also give me the equation to doing this one?)

(c) He then travels at uniform velocity a further 70m to the finish line. Calculate the time taken for the 70m and hence his total time for the 100m race.

(2)A jet aircraft has an acceleration of 6m.s-2. If initially the aircraft is travelling at 80 m.s-1, how long will it take to accelerate to 330 m.s-1 (the speed of sound)?

Thanks for the help :D

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# Homework Help: Motion Equation Help, Please

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