Question
Download Solution PDFA train crosses a point at a certain speed in 40 minutes. If the speed decreases by 10 km/h, it takes 48 minutes to cover the place. What was the initial speed of the train in km/h?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven:
Time taken at initial speed (t1) = 40 minutes
Time taken at reduced speed (t2) = 48 minutes
Change in speed (ΔV) = 10 km/h
Concept:
Since the train is crossing the same distance, we can use the formula relating times and speeds: Speed1/Speed2 = Time2/Time1.
Calculation:
Let's denote the initial speed as V1.
The reduced speed would then be (V1 - 10).
⇒ V1/(V1 - 10) = t2/t1
⇒ V1/(V1 - 10) = 48/40
Simplifying
V1/(V1 - 10) = 6/5
5V1 = 6V1 - 60
6V1 - 5V1 = 60
V1 = 60
∴ The initial speed of the train was 60 km/h.
Last updated on Nov 5, 2024
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