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A train is moving at a speed of 20 m/s and crosses a pole in 8 seconds. How long will it take to cross another train which is running in opposite direction at double speed and half the length of the first train?

A.

2 sec

B.

3 sec

C.

4 sec

D.

6 sec

Answer with explanation

Answer: Option CExplanation

Since the speed of the train is 20 m/s and it takes 8 seconds to cross the pole, so the length of the train is 20 × 8 = 160 metres

Now the other train is coming at double speed = 40 m/s and its length is half = 80 metres

So the total length to be crossed becomes = 160 + 80 = 240 meters

And the relative speed becomes 40 + 20 = 60 m/s

Therefore, the time taken = 240/60= 4 seconds

Workspace

Two trains 165 m and 135 m long run at the speed of 70 km/hr and 38 km/hr respectively in opposite directions on parallel tracks. The time (in seconds) which they take to cross each other is:

A.

6 sec

B.

8 sec

C.

10 sec

D.

14 sec

Answer with explanation

Answer: Option CExplanation

Workspace

A train started from point A at a speed of 60 km/hr and after 2 hours another train of same length started from A at a speed of 80 km/hr in the same direction as the first one. After how much time the second train will meet the first train?

A.

4 hours

B.

5 hours

C.

6 hours

D.

7 hours

Answer with explanation

Answer: Option CExplanation

Let after x hours the second train will meet the first train.

Because distance is same,

=> S_{1} t_{1} = S_{2} t_{2}

=> 60 (x + 2) = 80 × x

=> 60x + 120 = 80x

=> 80x – 60x = 120

=>20x = 120

=> x = 6 hours

Workspace

How many seconds will a 500 metre long train take to cross a man walking with a speed of 3 km/hr in the direction of the moving train if the speed of the train is 63 km/hr?

A.

30

B.

25

C.

20

D.

35

Answer with explanation

Answer: Option AExplanation

Speed of the train relative to man

Workspace

In what time will a train 100 meters long cross an electric pole, if its speed is 144 km/hr

A.

4 sec

B.

2.5 sec

C.

3 sec

D.

2 sec

Answer with explanation

Answer: Option BExplanation

First convert speed into m/sec

Speed = 144*(5/18) = 40 m/sec

Time = Distance/speed

= 100/40 = 2.5 seconds

Workspace

A train moves past a telegraph post and a bridge 264 m long in 8 seconds and 20 seconds respectively. What is the speed of the train?

A.

79.2 kmph

B.

79.3 kmph

C.

79 kmph

D.

79.1 kmph

Answer with explanation

Answer: Option AExplanation

Let the length of the train be *x* meters and its speed by *y* m/sec.

Then, *x*/*y* = 8

=> *x* = 8*y*

Now, [(*x* + 264)/20] = *y*

=> 8*y* + 264 = 20*y*

=> *y* = 22

∴ Speed = 22 m/sec = [22 × (18/5)] km/hr = 79.2 km/hr.

Workspace

Two trains running in opposite directions cross a man standing on the platform in 27 seconds and 17 seconds respectively and they cross each other in 23 seconds. The ratio of their speeds is?

A.

1 : 4

B.

3 : 2

C.

2 : 3

D.

1 : 2

Answer with explanation

Answer: Option BExplanation

Let the speeds of the two trains be x m/sec and y m/sec respectively.

Then, length of the first train = 27 x meters, and

length of the second train = 17 y meters.

(27 x + 17 y) / (x + y) = 23

=> 27 x + 17 y = 23 x + 23 y

=> 4 x = 6 y

=> x/y = 3/2 = 3 : 2

Workspace

Two stations A and B are 110 kms apart on a straight line. One train starts from A at 7 a.m and travels towards B at 20km per hour speed Another train starts from B at 8 a.m. and travels towards A at a speed of 25 Km per hour at what time will they meet?

A.

9 a.m

B.

12 a.m

C.

10 a.m

D.

11 a.m

Answer with explanation

Answer: Option CExplanation

Suppose they meet x hrs after 7 a.m

Distance covered by A in x hrs = (20 × x)

Distance covered by B in (x-1) hrs = 25 (x -1) km.

So they meet at 10 a.m.

Workspace

A jogger running at 9 kmph alongside a railway track is 240 meters ahead of the engine of a 120-metre long train running at 45 kmph in the same direction. In how much time will the train pass the jogger?

A.

34 sec

B.

32 sec

C.

38 sec

D.

36 sec

Answer with explanation

Answer: Option DExplanation

Speed of train relative to jogger = (45-9) = 36 kmph

===== >>>> 36*(5/18) = 10 m/sec

Distance to cover = 240 + 120 = 360 metres

Time = Distance/Speed

So,

======>>>>> Time = 360/10 = 36 sec

Workspace

Two trains of equal lengths take 10 seconds and 15 seconds respectively to cross a telegraph post. If the length of each train be 120 meters, in what time (in seconds) will they cross each other traveling in opposite direction?

A.

15

B.

20

C.

12

D.

10

Answer with explanation

Answer: Option CExplanation

Workspace

A train overtakes two persons who are walking in the same direction in which the train is going, at the rate of 2 kmph and 4 kmph and passes them completely in 9 and 10 seconds respectively. Find the length of train?

A.

60 m

B.

55 m

C.

50 m

D.

45 m

Answer with explanation

Answer: Option CExplanation

First person speed = 2*(5/18) = 5/9 m/sec

Second person speed = 4*(5/18) = 10/9 m/sec

Let the length of the train is x meter and speed is y m/sec

then,

So length of train is 50 metre

Workspace

A pilot flies an aircraft at a certain speed for a distance of 800 km. He could have saved 40 min by increasing the average speed of the plane by 40 km/h. Find the average speed of the aircraft.

A.

300 Km/h

B.

200 Km/h

C.

100 Km/h

D.

240 Km/h

Answer with explanation

Answer: Option BExplanation

Workspace

A train 110 metres long is running with a speed of 60 kmph. In what time will it pass a man who is running at 6 kmph in the direction opposite to that in which the train is going?

A.

10 sec

B.

7 sec

C.

6 sec

D.

5 sec

Answer with explanation

Answer: Option CExplanation

Workspace

A 300-meter long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform

A.

345 meters

B.

350 meters

C.

310 meters

D.

335 meters

Answer with explanation

Answer: Option BExplanation

Speed = Distance/time = 300/18 = 50/3 m/sec

Let the length of the platform be x meters

then

Workspace

A train crosses a platform of 150 m in 15 sec, the same train crosses another platform of length 250 m in 20 sec. then find the length of the train?

A.

150 m

B.

148 m

C.

136 m

D.

124 m

Answer with explanation

Answer: Option AExplanation

Length of the train be ‘X’

X + 150/15 = X + 250/20

4X + 600 = 3X + 750

X = 150m

Workspace

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