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Wed 9 Jun, 2004 02:04 pm
A man goes into a railway tunnel. When he's 1/4 way through he hears a train coming. Now, it's a very narrow tunnel, no room for him AND the train. So what should he do, go back or go forward.
IF he ran back, he would just get out before the train entered the tunnel, and if he ran forward he would just get out before train exited the tunnel.
If he was running at 12 mph., how fast was the train going ?
Which way is the train going? Sounds like from behind but please clarify.
The train is going the same way as the man
Kev, I had to laugh, half the distance in 12, twice in 24. Seems simple enough, on the same day I was sent this nightmare.
A train accelerates at a uniform rate from its starting point. It travels the last one fourth of the distance from the starting point to the finish line in 3 seconds. How long did it take to travel the entire distance from starting point to finish line?
There does not seem anywhere near enough information to form an answer. Can you assist?
Hi Try,
I suppose 45 secs would be too obvious an answer
Second Attempt at acceleration problem
d=kT^2 also .75d = k(T-3)^2
eliminating d gives the the quadratic
T^2 - 24T +36 = 0
T= 22.8 sec appx
Tryagain.
You don't seem to have used the general formula for the solution of a quadratic i.e.
If ax^2 + bx + c= 0,
then x =[ -b +\- sqrt (b^2 - 4ac)]/2a
This may explain the slight variation in our answers.
Regards fresco.
Tryagain,
I made a mistake using the formula !
Your answer is spot on.
"Your answer is spot on."
Which just goes to show, that if I try and tryagain, eventually I will get lucky.
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