Answer: Option D
Explanation:
Speed=  60 x  5  m/sec  =  50  m/sec.  
18  3 
Length of the train = (Speed x Time) =  50  x 9  m = 150 m.  
3 
2. 
A train 125 m long passes a man, running at 5 km/hr in the same direction in which the train is going, in 10 seconds. The speed of the train is:
 

Explanation:
Speed of the train relative to man =  125  m/sec  
10 
=  25  m/sec.  
2 
=  25  x  18  km/hr  
2  5 
= 45 km/hr.
Let the speed of the train be x km/hr. Then, relative speed = (x  5) km/hr.
x  5 = 45 x = 50 km/hr.
3. 
The length of the bridge, which a train 130 metres long and travelling at 45 km/hr can cross in 30 seconds, is:
 

Answer: Option C
Explanation:
Speed =  45 x  5  m/sec  =  25  m/sec.  
18  2 
Time = 30 sec.
Let the length of bridge be x metres.
Then,  130 + x  =  25 
30  2 
2(130 + x) = 750
x = 245 m.
4. 
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:
 

Answer: Option B
Explanation:
Let the speeds of the two trains be x m/sec and y m/sec respectively.
Then, length of the first train = 27x metres,
and length of the second train = 17y metres.
27x + 17y  = 23  
x+ y 
27x + 17y = 23x + 23y
4x = 6y
x  =  3  .  
y  2 
5. 
A train passes a station platform in 36 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?
 

Answer: Option B
Explanation:
Speed =  54 x  5  m/sec = 15 m/sec.  
18 
Length of the train = (15 x 20)m = 300 m.
Let the length of the platform be x metres.
Then,  x + 300  = 15 
36 
x + 300 = 540
x = 240 m.
Answer: Option B
Explanation:
Speed =  240  m/sec = 10 m/sec.  
24 
Required time =  240 + 650  sec = 89 sec.  
10 
7. 
Two trains of equal length are running on parallel lines in the same direction at 46 km/hr and 36 km/hr. The faster train passes the slower train in 36 seconds. The length of each train is:
 

Answer: Option A
Explanation:
Let the length of each train be x metres.
Then, distance covered = 2x metres.
Relative speed = (46  36) km/hr
=  10 x  5  m/sec  
18 
=  25  m/sec  
9 
2x  =  25  
36  9 
2x = 100
x = 50.
8. 
A train 360 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
 

Answer: Option A
Explanation:
Formula for converting from km/hr to m/s: X km/hr =  X x  5  m/s.  
18 
Therefore, Speed =  45 x  5  m/sec  =  25  m/sec.  
18  2 
Total distance to be covered = (360 + 140) m = 500 m.
Formula for finding Time =  Distance  
Speed 
Required time =  500 x 2  sec  = 40 sec.  
25 
9. 
Two trains are moving in opposite directions @ 60 km/hr and 90 km/hr. Their lengths are 1.10 km and 0.9 km respectively. The time taken by the slower train to cross the faster train in seconds is:
 

Answer: Option C
Explanation:
Relative speed = (60+ 90) km/hr
=  150 x  5  m/sec  
18 
=  125  m/sec.  
3 
Distance covered = (1.10 + 0.9) km = 2 km = 2000 m.
Required time =  2000 x  3  sec = 48 sec.  
125 
10. 
A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine of a 120 metres long train running at 45 kmph in the same direction. In how much time will the train pass the jogger?
 

Answer: Option C
Explanation:
Speed of train relative to jogger = (45  9) km/hr = 36 km/hr.
=  36 x  5  m/sec  
18 
= 10 m/sec.
Distance to be covered = (240 + 120) m = 360 m.
Time taken =  360  sec  = 36 sec.  
10 
11. 
A 270 metres long train running at the speed of 120 kmph crosses another train running in opposite direction at the speed of 80 kmph in 9 seconds. What is the length of the other train?
 

Answer: Option A
Explanation:
Relative speed = (120 + 80) km/hr
=  200 x  5  m/sec  
18 
=  500  m/sec.  
9 
Let the length of the other train be x metres.
Then,  x + 270  =  500 
9  9 
x + 270 = 500
x = 230.
12. 
A goods train runs at the speed of 72 kmph and crosses a 250 m long platform in 26 seconds. What is the length of the goods train?
 

Answer: Option D
Explanation:
Speed =  72 x  5  m/sec  = 20 m/sec.  
18 
Time = 26 sec.
Let the length of the train be x metres.
Then,  x + 250  = 20 
26 
x + 250 = 520
x = 270.
13. 
Two trains, each 100 m long, moving in opposite directions, cross each other in 8 seconds. If one is moving twice as fast the other, then the speed of the faster train is:
 

Answer: Option C
Explanation:
Let the speed of the slower train be x m/sec.
Then, speed of the faster train = 2x m/sec.
Relative speed = (x + 2x) m/sec = 3x m/sec.
(100 + 100)  = 3x  
8 
24x = 200
x =  25  . 
3 
So, speed of the faster train =  50  m/sec 
3 
=  50  x  18  km/hr  
3  5 
= 60 km/hr.
14. 
Two trains 140 m and 160 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time (in seconds) which they take to cross each other, is:
 

Answer: Option D
Explanation:
Relative speed = (60 + 40) km/hr =  100 x  5  m/sec  =  250  m/sec.  
18  9 
Distance covered in crossing each other = (140 + 160) m = 300 m.
Required time =  300 x  9  sec  =  54  sec = 10.8 sec.  
250  5 
15. 
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?
 

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