A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train?
120 metres
180 metres
324 metres
150 metres Answer: Option
Explanation:
Speed = 60 x 5 m/sec = 50 m/sec.
18 3
Length of the train = (Speed x Time).
Length of the train = 50 x 9 m = 150 m
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A train is running at sixty kilometers per hour and crosses a pole in nine seconds. We need to find the length of the train. When a train crosses a pole, the distance traveled equals the train's length.
First, we need to convert the speed from kilometers per hour to meters per second. We multiply by the conversion factor five eighteenths. Sixty kilometers per hour times five eighteenths equals three hundred divided by eighteen, which equals fifty thirds meters per second.
Step two: we apply the distance formula. Distance equals speed times time. The length of the train equals fifty thirds meters per second times nine seconds. This gives us fifty times nine divided by three, which equals four hundred fifty divided by three, equals one hundred fifty meters.
The final answer is one hundred fifty metres, which corresponds to option D. To summarize our solution: we converted the speed from sixty kilometers per hour to fifty thirds meters per second, then applied the distance formula where length equals speed times time, giving us one hundred fifty metres. Remember, when a train crosses a pole, the distance traveled equals the train's length.
To summarize what we have learned: speed conversion is essential when solving motion problems, always multiply kilometers per hour by five eighteenths to get meters per second. The distance formula is fundamental in these calculations. When a train crosses a pole, the distance traveled equals the train's length. Remember to always convert units before calculating to avoid errors.