A_____________________B
100 km
Ok, you have two trains. One is starting to chu-chu from point A, and the other one from point B. Length of the rail is 100 km. First is going via speed of 40km/h, and the other is traveling via speed of 60 km/h. Now, you have a bird...The bird is flying from point A to point B, and when it reaches point B it flyies to point A, and so on...The bird is traveling with speed of 90km/h. The big question is...What is the distance that will the bird fly over, before the two trains colide?
2006-09-16 06:45:06 · 12 answers · asked by :? 1 in Science & Mathematics ➔ Mathematics
The bird has 10km left to fly before the two trains crash. So 90 km.
2006-09-16 06:50:34 · answer #1 · answered by *babydoll* 6 · 0⤊ 0⤋
I think that as the first train is traveling at 40 km/h and the other one at 60 km/h so thier relative velocity is 100 km/h. The two trains will meet at the 40 km mark or the 60 km mark depending on your starting point. They will cover that distance in 1 hour. The speed of the bird is 90 km/h so when the trains collide the birdie wont even have reached the other point B if it started from A.
So when the trains collide the bird will be at the 90 km mark from A, as you mentioned it starts from A.
2006-09-16 06:56:56 · answer #2 · answered by the.chosen.one 3 · 0⤊ 0⤋
90 km
train 1 goes 40 km in 1 hour
train 2 goes 60 km in 1 hour
60 +40=100 ....so they collide in 1 hour
the bird flies 90km in 1 hour
2006-09-16 06:47:26 · answer #3 · answered by Gandalf 3 · 0⤊ 0⤋
90km
The trains collide at the 1 hour point at which time the bird had gone 90km. The bird does not get to point B, but is 10km short when the trains hit at the 1 hour mark at the point 40km from point A and 60km from point B.
Or is this a trick question?
2006-09-16 06:54:56 · answer #4 · answered by rowlfe 7 · 0⤊ 0⤋
It would be just over 90 km as the bird would be up to speed faster presuming the two trains were stationary and additional distance over the obvious 90 km would depend on the acceleration of the two trains.
2006-09-16 06:50:07 · answer #5 · answered by g8bvl 5 · 0⤊ 1⤋
Come on!
What is everyone's obsession with these silly train problem?
The two trains have to cover a combined distance of 100km before colliding. They have a combined speed of 60+40 = 100km/h. Thus they will cover the 100km in one hour.
The bird flies at 90km/h so it covers 90km in the one hour it takes the trains to meet.
90km!
2006-09-16 06:47:51 · answer #6 · answered by selket 3 · 0⤊ 0⤋
90 km
The trains collide after one hour. The bird flies 90 km/h
2006-09-16 06:48:43 · answer #7 · answered by Enduringwisdom 4 · 0⤊ 0⤋
simple...
the trains meet after 100/(40+60)=1 hr
so the bird has flown for 1 hr - no more, no less.... hence covering 90 km
2006-09-16 06:50:24 · answer #8 · answered by m s 3 · 0⤊ 0⤋
1 1/2 times across before they colide.
2006-09-16 06:48:35 · answer #9 · answered by lovebug 1 · 0⤊ 1⤋
the bird wont make it to B once before they will colide . right ?
2006-09-16 06:47:47 · answer #10 · answered by Milos K 4 · 0⤊ 0⤋