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3 years ago

Why does an object under forced convection reach a steady-state faster than an object subjected to free-convection?

Engineering

1 answer:

bonufazy [111]3 years ago

5 0

Answer:

Free convection:

When heat transfer occurs due to density difference between fluid then this type of heat transfer is know as free convection.The velocity of fluid is zero or we can say that fluid is not moving.

Force convection:

When heat transfer occurs due to some external force then this type of heat transfer is know as force convection.The velocity of fluid is not zero or we can say that fluid is moving in force convection.

Heat transfer coefficient of force convection is high as compare to the natural convection.That is why heat force convection reach a steady-state faster than an object subjected to free-convection.

We know that convective heat transfer given as

q = h A ΔT

h=Heat transfer coefficient

A= Surface area

ΔT = Temperature difference

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2 years ago

An inductor has a 50.0-Ω reactance when connected to a 60.0-Hz source. The inductor is removed and then connected to a 45.0-Hz s

nignag [31]

Given:

$X_{L} = 50.0 \ohm$

frequency, f = 60.0 Hz

frequency, f' = 45.0 Hz

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Solution:

To calculate max current in inductor, $I_{L(max)$ :

At f = 60.0 Hz

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$50.0 = 2\pi\times 60.0\times L$

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Now, reactance $X_{L}$ at f' = 45.0 Hz:

$X'_{L} = 2\pi f'L$

$X'_{L} = 2\pi\times 45.0\times 0.13263 = 37.5\ohm$

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2 years ago

1. ELECTRICAL SHOCK

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Here’s some of them
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13. F
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3 years ago

1. A team of students have designed a battery-powered cooler, which promises to keep beverages at a high-drinkability temperatur

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Answer:

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Explanation:

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To get the minimum electrical power required, use the relation below:

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2 years ago

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Alja [10]

Answer:

Explanation:

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in equation (iii)

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3 years ago