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Ugo [173]
3 years ago
7

If a train is 100 kilometers away, how much sooner would you hear the train coming by listening to the rails (iron) as opposed t

o listening for it standing by the track? In other words, how much faster will the sound travel through the iron rails than through the air? Assume the air temperature is 0°C. Sound will reach you seconds sooner.
Physics
1 answer:
Whitepunk [10]3 years ago
6 0
From tables, the speed of sound at 0°C is approximately
V₁ = 331 m/s (in air)
V₃ = 5130 m/s (in iron)

Distance traveled is
d = 100 km = 10⁵ m

Time required to travel in air is
t₁ = d/V₁ = 10⁵/331 = 302.12 s

Time required to travel in iron is
t₂ = d/V₂ = 10⁵/5130 = 19.49 s

The difference in time is
302.12 - 19.49 = 282.63 s

Answer:  283 s (nearest second)



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Answer:

Explanation:

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Here, P and Q are in series.

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6 0
3 years ago
All of the following are physical properties of hydrogen peroxide except it
tankabanditka [31]
The answer to this question is B, Reacts with sunlight.

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Meanwhile, for chemical properties, they're about how the substance reacts with other substances, such as metals react with acid to form hydrogen. And by the word "react", it means there's no way turn the reaction product back to the original substance without using chemical methods such as heating or electrolysis. 

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5 0
3 years ago
The 10-kg uniform rod is pinned at end
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Answer:

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D= 4 mm

K = 160 W/m-K

h=h = 220 W/m²-K

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By solving above equation we get

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