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2 years ago

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When the volcano Krakatoa erupted in 1883, it was heard 5000 km away. Which statement about the sound from the volcano is not co

rrect?
a. If such a loud sound were to be made today, an astronaut orbiting in space (a vacuum) at a height of 400 km could hear it.
b. People further from the volcano heard the sound later than people nearer to the volcano.
c. The amplitude of the sound waves would have been smaller further from the volcano.
d. The sound was very loud because a lot of energy was transferred to vibrations of the air.

1 answer:

lina2011 [118]2 years ago

7 0

Answer a) is incorrect as sound does not travel in a vacuum.

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In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

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where,

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$m_1$ = mass of copper = 120 g

$m_2$ = mass of water = 300 g

$T_f$ = final temperature of mixture = $35^oC$

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$T_2$ = initial temperature of water = $15^oC$

Now put all the given values in the above formula, we get:

$120g\times 0.10cal/g^oC\times (35-T_1)^oC=-300g\times 1.00cal/g^oC\times (35-15)^oC$

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Therefore, the temperature of the kiln was, $535^oC$

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2 years ago

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2 years ago