A bus moves from station A to B with a speed of 50 km/h travelling dis...
Problem:
A bus moves from station A to B with a speed of 50 km/h travelling distance 10 km. Then the driver increases the speed up to 60 km/h. One of the passengers asks the driver to decrease the speed of the bus because as per traffic rules maximum speed for a heavy vehicle is 40 km/h after 6 minutes moving with the speed of 60 km /h it reaches station C which is 12 km from station B. If the average speed of the bus is 40 km/h what is the speed of the bus between station C to D? C Explain in details.
Solution:
Step 1: Calculate the time taken to travel from station A to B
Distance from station A to B = 10 km
Speed of the bus = 50 km/h
Time taken to travel from station A to B = Distance / Speed = 10 km / 50 km/h = 0.2 hours = 12 minutes
Step 2: Calculate the time taken to travel from station B to C
Distance from station B to C = 12 km
Speed of the bus = 60 km/h
Maximum speed for a heavy vehicle = 40 km/h
Time taken to travel at 60 km/h = Distance / Speed = 12 km / 60 km/h = 0.2 hours = 12 minutes
Time taken to travel at 40 km/h = Distance / Speed = 12 km / 40 km/h = 0.3 hours = 18 minutes
Time taken to decrease the speed from 60 km/h to 40 km/h = 18 - 6 = 12 minutes
Time taken to travel from station B to C with a speed of 60 km/h for 6 minutes and 40 km/h for 12 minutes = 6/60 + 12/40 = 0.15 + 0.3 = 0.45 hours = 27 minutes
Step 3: Calculate the time taken to travel from station C to D
Time taken to travel from station A to C = 12 + 27 = 39 minutes
Time taken to travel from station C to D = Total time taken - Time taken to travel from station A to C = 60 - 39 = 21 minutes
Step 4: Calculate the speed of the bus between station C to D
Distance from station C to D = 10 km
Time taken to travel from station C to D = 21 minutes = 0.35 hours
Speed of the bus between station C to D = Distance / Time = 10 km / 0.35 hours = 28.57 km/h
Answer:
The speed of the bus between station C to D is 28.57 km/h.