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3 years ago

If a certain mass of mercury has a volume of 0.002 m3 at a temperature of 20°C, what will be the volume at 50°C?

1 answer:

Klio2033 [76]3 years ago

5 0

From tables, the density of mercury is
13545 kg/m^3 at 20°C,
13472 kg/m^3 at 50°C.

Because mass = density * volume, the mass of mercury at 20°C is
m = (13545 kg/m^3)*(0.002 m^3) = 27.09 kg

Let V = volume of mercury at 50°C.
Because the mass of mercury does not change, therefore at 50°C,
(13472 kg/m^3)*(V m^3) = 27.09
V = 27.09/13472 = 0.0020108 m^3

Answer: B. 0.002010812 m³

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Answer:

<h2>The answer is </h2><h2>C. a paved road</h2>

Explanation:

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Paved roads are roads that are covered with a firm surface suitable for travel, like paving stones or concrete or asphalts.

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3 years ago

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Answer:

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3 years ago

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As the ball goes up, its speed decreases, so its kinetic energy decreases and converts into gravitational potential energy. When the ball reaches its maximum height, the speed has become zero, and all the kinetic energy has been converted into gravitational potential energy, given by:

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Since we can ignore air resistance, energy must be conserved, so the initial kinetic energy must be equal to the final potential energy of the ball, so we can write:

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3 years ago

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3 years ago

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Answer:

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Hope this helped!

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3 years ago