Ratio of Speeds Train Problems Formula
In this class, We discuss Ratio of Speeds Train Problems Formula.
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If two trains are bodies, start simultaneously from points A and B towards each other.
After passing each other, they take b and a second to reach B and A, respectively.
A’s speed: B’s Speed = √b: √a
The below diagram shows the graphical intuition of the example.
Important: The two trains meet at some point.
The time traveled before the two trains meet t seconds.
The above point helps in solving the formula and helps in solving the bits.
After the two trains met, Train A traveled seconds to reach B.
Train B traveled b seconds to reach A.
Assumption: The speed of the train started at A is ‘u’ m/s.
The speed of the train started at B is v m/s.
The two trains meet at a point. When the two trains met, they covered the distance from A to B.
Distance from A to B is x.
Distance = speed * Time
x = t (u+v) equation 1
x = (t+a)u equation 2
x = (t+b)v equation 3
Equate 1 and 2 equations.
ut + vt = ut + ua
vt = ua
Equate 1 and 3 equations.
ut + vt = vt + vb
ut = vb
t = vb/u
Substituting we get
v(vb/u) = ua
v^2 b = u^2 a
u/v = √b/√a