# distance/time problem

by michael makepeace
(Newcastle UK)

After the brakes are applied, the distance a train travels before coming to rest varies as the square of the speed of the train at the instant the brakes are applied. A train passing a signal box has to stop at a signal 1200 yards beyond the box. In order to do this when it is travelling at 60 m.p.h., the brakes must be applied when it is level with the box.

Calculate
(i) how far in front of the box the brakes must be applied when the train is travelling at 63 m.p.h,
(ii)how many seconds, to the nearest second, can elapse after passing the box, before the brakes have to be applied, when the train is travelling at 45 m.p.h.

Find a Math Word here

Can't find the word you are looking for? Do a search here and type your word in the box below

Good, better best.

Never, ever rest.

Like this website?

"I am getting much better test marks and I have been moved up a set"
Sumera
Age 13
England

"High school's great, I'm in a good math set and I understand lots of things, thanks to you"
Eleanor Talbot
Age 11
England

"I really like math now, you just make it more friendly and normal"
Jess Johnson
Age 18
England

"Your writing style is great, informative but friendly! My 12 year old son still struggles with basic maths. I can see your website will be a real treasure trove for us :)"
Jackie
New Zealand