A train passing a stationary pole takes 8 seconds, and it requires 20 seconds to completely pass a 240-meter long platform. Find the speed of the train in km/h. MCQ with Answer and Explanation
A train passing a stationary pole takes 8 seconds, and it requires 20 seconds to completely pass a 240-meter long platform. Find the speed of the train in km/h.
A. 68 km/h
B. 76 km/h
C. 72 km/h
D. 80 km/h
Answer: Option C
Solution (By JKSSB Mock Tests)
Time taken to cross the platform distance alone = 20 - 8 = 12 seconds. Speed of train = 240 / 12 = 20 m/s. In km/h = 20 * (18/5) = 72 km/h.
Two stations A and B are 450 km apart. A train leaves station A at 4:00 PM at 60 km/h. Another train leaves station B at 5:00 PM at 70 km/h traveling towards A. At what time will they meet?
Explanation:
By 5:00 PM, the first train has traveled for 1 hour and covered 60 km. Distance left between them = 450 - 60 = 390 km. Relative speed = 60 + 70 = 130 km/h. Time to meet after 5:00 PM = 390 / 130 = 3 hours. Meeting time = 5:00 PM + 3 hours = 8:00 PM.
Explanation:
New speed = 4/5 of usual speed => New time = 5/4 of usual time. Difference = 1/4 of usual time = 12 minutes. Usual time = 12 * 4 = 48 minutes.
No comments yet. Be the first to start the discussion!