Time = Total distance / Relative speed
4.5/60 hr. = (450/1000) / x
? x = 6 km/h
Relative speed = Speed of car - Speed of man
6 = x - 6
? x = 12 km/h
(speed of wind) / (speed of car) = (Time utilised) / (time saved)
? 332/x = 332/28
? x = 28 m/s
Circumferences means one resolutions .
Therefore, distance covered in 10 resolutions =300 x 10 = 30 m
i.e., 30 meters in 6 seconds.
? Speed of wheel = 30/6 m/s = 5 m/s
? 5 m/s = 5 x (18/5) = 18 km/h
Let the length of train be x m, then
x/10 = (120 + x)/18
? x = 150m
Relative speed = 50 - 40 = 10 km/h = 50/18 m/s
? Time taken = Sum of length of the trains / Relative speed
= (200/50) x 18 = 72 sec.
Relative speed = 20 + 1 = 21 km/h = 21 x 5/18 = 35/6 m/s
Time = Length of train / Relative speed = (350/35) x 6 = 60 s
Let they meet after x h.
Then, according to the question,
3x + 4x = 17.5
? 7x = 17.5
? x = 17.5 / 7 = 2.5 h
So, they meet 2.5 h after 8:00 am.
It means they meet at 10:30 am.
Let distance between Manipur and Dispur = D km
Average speed of train from Manipur = D/4 km/h
Average speed of train from Dispur = 2D/7 km/h
Let they meet T h after 6:00 am.
Then, according to the question,
(D/4 x T) + 2D/7 x (T - 2) = D
? T/4 + 2(T - 2)/7 = 1
? 7T + 8(T - 2) = 28
? 15T = 44
? T = 44/15 h = 2h 56 min
Clearly, trains meet 2 h 56 min after 6:00 am.
It means the trains meet at 8:56 am.
Let the distance traveled on foot be x km
Then, distance converted by bicycle = (45 - x) km
? x/3 + (45 -x) /8 = 83/4 = 35/4
? (8x + 135 - 3x)/24 = 35/4
? 5x + 135 = 210
? 5x = 75
? x = 15
? Distance converted by bicycle = (45 - 15) = 300 km
Suppose length of the train = L m
Speed of the train = 60 km/h = 60 x 1000 = 60000 m/h
Length of tunnel = 1.5 km = 1500 m
Time taken by train = 2 min = 1/30 h
Time = Distance/Speed
? 1/30 = L + 1500/60000
? l = 500 m
Let the speed of the train during returning journey be x km/h
Speed during onward journey = x + 25x/100 = 5x/4 km/h.
Distance coverd in onward journey = 800 / 2 = 400 km
Total time taken = Covered distance / Speed
Time taken by train in onward journey = 400/(5x/4)
and time taken in returning journey = 400/x
Thus, 400/(5x/4) + 400/x = 16
? 320/x + 400/x = 16
? 16x = 720
? x = 45 km/h
Speed of the train in the onward journey = 5 x 45/4 = 56.25 km/h
Comments
There are no comments.Copyright ©CuriousTab. All rights reserved.