Speed of train = 60 km/h = 60 x (5/18) m/s = 50/3 m/s
Let length of the platform be L m.
According to the question,
200 + L = (50/3) x 30
? 200 + L = 500
? L = 300 m
Let length of bridge be L m.
We know, Speed = Distance/Time
According to the question,
90 x 5/18 = 150 + L/26
? 25 x 26 = 150 + L
? 650 = 150 + L
? L = 500 m
Speed of train = Length of train / Time taken to cross the stationary object
? Length of train = Speed of train x Time taken to cross the stationary object
= 72 x 5 x (15/18) = 300 m
Let the length of the train be L m.
New , speed = 48 km/h = 48 x (5/18) m/s
Train takes 9 s to cross a pole.
? : Length of train, L = Speed x Time
= 48 x (5/18) x 9 = 120 m
Given t1 = 16 h , t2 = 9 h and a = 90 km/h
According to the question
? Speed of B = a?t1/ t2
= 90 x ?16/9
= 90 x 4/3
= 30 x 4 = 120 km/h
Let the length of the first train be x m.
Then, the length of second train is (x/2) m
? Relative speed = (48 + 42) km/h = (90 x 5/18) m/s = 25 m/s
According to the question. (x + x/2) / 25 = 12
? 3x/2 = 300
? x = 200 m
? Length of first train = 200 m
Let the length of platform be y m .
Speed of the first train = (48 x 5/18) m/s = 40/3 m/s
Time = Distance / Speed
? (200 + y) x 3/40 = 45
? 600 + 3y = 1800
? y = 400 m
Let the length of the train be L m.
According to the question,
L/9 = Speed ...(i)
and (L + 150)/15 = Speed ..(ii)
from Eqs. (i) and (ii) we get
L/9 = (L + 150)/15
? L/3 = (L + 150)/5
? 5L = 3L + 450
? L = 225 m
Let length of the train be L m.
According to the question,
L/2 = (L + 250)/7
? 7L = 2L + 500
? 7L - 2L = 500
? 5L = 500
? L = 500/5 = 100 m
Let length of both train and platform be L.
Distance covered by the train to cross the platform = L + L = 2L
Time =1 min = 60 s
and speed = 90 km/h = 90 x 5/18 = 25 m/s
? Distance = Speed x Time
? 2L = 25 x 60
? L = 750 m
Let length of the train = L
According to the question,
(L + 300)/21 = (L + 240)/18
? (L + 300)/7 = (L + 240)/6
? 6L + 1800 = 7L + 1680
? L = 120 m
Taking the length of the 2nd bridge into consideration,
Speed of train = (L+ 240)/18 = (120 + 240)/18 m/s
= (360/18) x (18/5) km/h
= 72 km/h
According to the formula .
Required time = (x + y) / (u + v)
Here, x = 70 m, y = 90 m, u = 10 m/s and v = 6 m/s
? Required time = (70 + 90) / (10 + 6) = 160/16 = 10 s
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