A 100 m long train is travelling from North to South at a speed of 30

1.	A 100 m long train is travelling from North to South at a speed of 30 ms-1. A bird is flying from South to North at a speed of 10-1. How long will the bird take to, cross the train?(a) 3 s (b) 2.5 s(c) 10 s (d) 5 s
Answer» (b) Length of train = 100 m Relative velocity = 30+ 10 = 40 ms^-1 Time taken to cross the train (t) = \(\frac{distnace}{R.velocity}\) = \(\frac{100}{40}\) =2.5 s

A 100 m long train is travelling from North to South at a speed of 30 ms-1. A bird is flying from South to North at a speed of 10-1. How long will the bird take to, cross the train?(a) 3 s (b) 2.5 s(c) 10 s (d) 5 s

Answer»

(b) Length of train = 100 m

Relative velocity = 30+ 10 = 40 ms^-1

Time taken to cross the train (t) = \(\frac{distnace}{R.velocity}\) = \(\frac{100}{40}\) =2.5 s

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A 100 m long train is travelling from North to South at a speed of 30 ms-1. A bird is flying from South to North at a speed of 10-1. How long will the bird take to, cross the train?(a) 3 s (b) 2.5 s(c) 10 s (d) 5 s

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