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8090 [49]
3 years ago
10

Given that coal used by electric power plants has a heating value of 27.5 million btus metric ton (25 million btus per ton), det

ermine the number of kilograms (and pounds) of coal needed to produce 1 million btus of heat.
Physics
1 answer:
fredd [130]3 years ago
3 0

Answer:

• 36.4 kg of coal.

• 80 pounds of coal.

Explanation:

Using proportionality constant,

Mass of coal = 1,000,000/27,500,000 btus/metric ton

= 0.0364 metric tons of coal

Mass of coal = 1,000,000/25,000,000 btus/ton

= 0.04 tons of coal.

Converting metric tons to kilogram,

1 metric ton = 1000kg,

0.0364 metric ton;

= 36.4 kg of coal.

Converting tons to pounds,

1 ton = 2000 pounds,

0.04 metric ton;

= 80 pounds of coal.

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Answer:

Fad = 28.8 kN

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Explanation:

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AD = √10.5 m

AD ≈ 3.24 m

BD = √((1.5 m)² + (1 m)² + (2.5 m)²)

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CD = √8.25 m

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Fbdz = 2.5 / 3.08 Fbd = 0.811 Fbd

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∑Fy = ma

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∑Fz = ma

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Substitute into either of the first two equations:

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Answer:

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