Let length of bridge be L m.
We know, Speed = Distance/Time

According to the question,
90 x 5/18 = 150 + L/26

Correct Option: A

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

Correct Option: C

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

Correct Option: B

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

Correct Option: A

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

Correct Option: A

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