A train 250 meters long is running at a speed of 90 km/h. How long will it take to cross a platform 150 meters long?
A
24 seconds
B
28 seconds
C
16 seconds
D
30 seconds
উত্তরের বিবরণ
Question: A train 250 meters long is running at a speed of 90 km/h. How long will it take to cross a platform 150 meters long?
Solution:
speed = 90 km/h = 90 × (5/18) m/s
= 25 m/s
To cross the platform have to travel = (250 + 150) m
= 400 m
∴ Required time = 400/25 seconds
= 16 seconds
0
Updated: 1 month ago
A boat can travel 48 km upstream in 6 hours. If the speed of the stream is 2 km/hr, how much time will the boat take to cover a distance of 120 km downstream?
Created: 1 month ago
A
20 hours
B
18 hours
C
10 hours
D
19 hours
Question: A boat can travel 48 km upstream in 6 hours. If the speed of the stream is 2 km/hr, how much time will the boat take to cover a distance of 120 km downstream?
Solution:
Distance covered by a boat in 6 hours = 48 km
Rate upstream of boat = 48/6
= 8 km/hr
Now,
Speed of stream = 2 km/hr
∴ Speed of boat in still water = (8 + 2)
= 10 km/hr
∴ Rate downstream of boat = (10 + 2) km/hr
= 12 km/hr
∴ Time taken in covering 120 km distance = 120/12
= 10 hours
0
Updated: 1 month ago
An aeroplane covers a certain distance at a speed of 250 kmph in 6 hours. To cover the same distance in 100 minutes, it must travel at a speed of-
Created: 1 month ago
A
900 km/hr
B
700 km/hr
C
800 km/hr
D
950 km/hr
Question: An aeroplane covers a certain distance at a speed of 250 kmph in 6 hours. To cover the same distance in 100 minutes, it must travel at a speed of-
Solution:
Total Distance = (250 × 6) = 1500 km.
Time 100 minutes = 100/60 hr
= 5/3 hr
We know that,
Speed = Distance/Time
∴ Required speed = 1500/(5/3) km/hr
= 900 km/hr.
0
Updated: 1 month ago
A train passes a man at 110 kmph running towards the train at the speed of 10 kmph. If it took 3 seconds to cross the man, what would be the length of the train?
Created: 1 month ago
A
300 m
B
100 m
C
250 m
D
180 m
Question: A train passes a man at 110 kmph running towards the train at the speed of 10 kmph. If it took 3 seconds to cross the man, what would be the length of the train?
Solution:
As both of them are facing towards each other.
total speed will be = 110 + 10 kmph
= 120 kmph
length of the train = 120 × (3/3600) km
= 0.1 km
= 100 m
0
Updated: 1 month ago
