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3 years ago

7

Thiết bị trao đổi nhiệt ngược chiều, nhiệt độ chất lỏng nóng vào là 310°C, ra là 115°c. Nhiệt độ chất lỏng lạnh vào là 25°c và r

a là 68°c. Hãy tính độ chênh lệch nhiệt độ trung bình ∆t(m)

1 answer:

Vika [28.1K]3 years ago

5 0

Answer: 129.5 m

Explanation:

310 + 115 + 25 + 68 = 518

518 / 4 = 129.5 m

i think. Sorry if this is wrong

:)

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Answer:

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3 years ago

A 20 kg crate initially at rest on a horizontal floor requires a 80 N horizontal force to set it in motion. Find the coefficient

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Answer:

<em>The coefficient of static friction between the crate and the floor is 0.41</em>

Explanation:

<u>Friction Force</u>

When an object is moving and encounters friction in the air or rough surfaces, it loses acceleration and velocity because the friction force opposes motion.

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$Fr=\mu N$ [1]

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If no forces other then the weight and the normal are acting upon the y-direction, then the weight and the normal are equal in magnitude:

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We can find the coefficient of static friction by solving [1] for $\mu$ :

$\displaystyle \mu=\frac{Fr}{N}$

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3 years ago

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CT is a painless, noninvasive way for your healthcare provider to diagnose conditions.

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2 years ago

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Answer:

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3 years ago

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3 years ago