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Sauron [17]
3 years ago
8

A train travels 57 kilometers in 3 hours, and then 87 kilometers in 2 hours. What is its average speed? km/hr

Physics
1 answer:
skad [1K]3 years ago
3 0
Average speed (v) = total distance(d) / total time (t)
d = 57 + 87km = 144km
t = 2 + 3hrs = 5hrs
v = d÷t = 144÷5 = 28.8km/hr
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Answer:

\Delta L = 4.2 m

Explanation:

As per the formula of thermal expansion we know that

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so here we will have

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so here change in the length of the rod is given as

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\Delta L = 1400 (12 \times 10^{-6})(250)

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3 years ago
1. A man travels 45 m in 35 seconds. How fast is that?<br> What’s the answer
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What quantity is scalar
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A scalar quantity is a measurement of a quantity, like temperature, or mass.

5 0
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A sinusoidal wave of angular frequency 1,203 rad/s and amplitude 3.1 mm is sent along a cord with linear density 3.9 g/m and ten
kobusy [5.1K]

Answer:

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Answer:

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