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A question my son was given.
An electric train accelerates uniformly from rest, to reach 55km /p/h in 6mins.
Determine the total time taken to travel 10km.
An electric train accelerates uniformly from rest, to reach 55km /p/h in 6mins.
Determine the total time taken to travel 10km.
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If you can work out how far it's travelled in 6 mins it should be easy. I can't !
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6 minutes 45 seconds. (I think).
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If it's on the Jubilee Line, about three f**king hours.
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Wheres Mart when you need him . ??
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Are you sure OP's son read the question right? Six minutes to accelerate to 55 kph seems absurdly slow.
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his sons only 7
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I will guess 6mins 58 seconds
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Howard, neither can I lol
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as ram says...approx 2 min to get to 11mph..another 2 mins to reach 23mph..another 2 mins to reach 34mph..
maybe thats irrelevant and its only for the purpose of the calculation. | ||||
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I was thinking, probably miles out but if you work it out per second 55 divided by 360, gives you 0.152 km per second.
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then again I got a D for Maths O'Grade
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Is the answer "FISH" ?
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I got 0 level maths, far too long ago now though...even the grandsons homework is hard lol
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https://www.youtube.com/watch?v=s71atR_VHPs
A little something like what I wrote earlier!  | ||||
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For the first 6 minutes the train averaged 55/2 km/ph, (the average between 0 km/ph and 55 km/ph) and so would have travelled 2.75 kms in the 6 minutes. That leaves 7.25 kms to go at 55 km/ph which would take approx another 7.9 minutes. So the 10km journey will have taken 6 minutes plus 7.9 minutes making a total of 13.9 minutes.
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Yeah, that's right. I forgot to divide the first half by 2 so had it travelling twice as far as it was meant to do in the first six minutes.
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Exactly
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Aye leave it to the experts, all makes sense now
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Need more information here ?
What sort of snow is on the line please ? | ||||
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Cheers uwgs.
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Dealer, you sound like me lol
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Is that correct? The train reached 55km/p/h accelerating uniformly, aren't you assuming that it will travel at 55km/p/h for the rest of the journey?
Can't recall velocity from donkeys years ago but i assumed the train would continue to accelerate. | ||||
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Just a slight dent in uwg methodology
If the average was 55kph then it must have travelled faster at some point The question doesnt quote the average though GL | ||||
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Surprised you don't know the answer Koi
Being red hot at point to point | ||||
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average wasn't 55.....max was.....uwg is correct
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he said averaged 55/2 which is 27.5 kmph
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just out of interest , where was the train going ?
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It takes 6 min to reach 55km/hr and covers 2.75km......leaving 7.25 km to go @55km/hr.
i.e. 7.91 mins...total time 13.91 mins.. | ||||
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Think of it like this...the end velocity is 55km/hr,....or approx 1 km /min.
So, to cover the whole 10 @1km/ min would take 10 mins...but its first got to reach the end speed which takes 6 min. This takes up 2.75 km...leaving 7.25 @approx 1 km/min... | ||||
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Maths is not in question
Assumption of top speed is Call Stewart R for the defence Old proverb once told - Assume makes an ass of u and me Was it an essential journey btw & did they have any egg & cress sandwiches available Stick to me times tables | ||||
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11 minutes 26.49secs to 2dp
work in metres and seconds using v = u + at and s=ut+at^2/2 starts from rest so u = 0 we know v (55kph at time t 6 minutes, hence derive a) want t at s= 10k so plug in derived a and derive t | ||||
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What's the voltage and how big is tthe flux capacitor
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9.166666666666 mins would be the answer I think they are looking for but it's prob completey wrong, not had a look at the replies yet,the lack of info in the question is typical of school **** now.
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What age group is this for?
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Oops
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It only asks how long to travel 10km, not how long to travel the first 10km of a journey.Its a trick question imo.
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