Difficulty: Easy
Correct Answer: 15
Explanation:
Introduction / Context:Across a platform, total distance equals train length plus platform length. Divide by time to get speed in m/s directly, since distances are in metres and time in seconds.
Given Data / Assumptions:
Concept / Approach:S = 50 + 100 = 150 m. Speed v(m/s) = S/t = 150/10 = 15 m/s.
Step-by-Step Solution:
S = 150 m.v = 150/10 = 15 m/s.Verification / Alternative check:Converting to km/h: 15 * 3.6 = 54 km/h; plausible for an urban/slow intercity scenario.
Why Other Options Are Wrong:10 is too low; 50 and 150 are not realistic m/s here; 12 results from 120 m assumption.
Common Pitfalls:Using only train length for a platform case; unit conversion when not required.
Final Answer:15
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