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2 years ago

What is the physical significance of the Reynolds number?. How is defined for external flow over a plate of length L.

Engineering

1 answer:

yanalaym [24]2 years ago

7 0

Answer:

$Re=\dfrac{\rho\ v\ l}{\mu }$

Explanation:

Reynolds number:

Reynolds number describe the type of flow.If Reynolds number is too high then flow is called turbulent flow and Reynolds is low then flow is called laminar flow .

Reynolds number is a dimensionless number.Reynolds number given is the ratio of inertia force to the viscous force.

$Re=\dfrac{F_i}{F_v}$

For plate can be given as

$Re=\dfrac{\rho\ v\ l}{\mu }$

Where ρ is the density of fluid , v is the average velocity of fluid and μ is the dynamic viscosity of fluid.

Flow on plate is a external flow .The values of Reynolds number for different flow given as

$Reynolds\ number\is \ >\ 5 \times 10 ^5\ then\ flow\ will\ be\ turbulent.$

$Reynolds\ number\is \$

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It is the tool used to measure the amount of electric current

sergeinik [125]

Answer:

Ammeter

Explanation:

Instrument for measuring either direct or alternating electric current, in amperes. Ammeters vary in their operating principles and accuracies

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2 years ago

Read 2 more answers

(a) Determine the dose (in mg/kg-day) for a bioaccumulative chemical with BCF = 103 that is found in water at a concentration of

solmaris [256]

Answer:

0.064 mg/kg/day

6.25% from water, 93.75% from fish

Explanation:

Density of water is 1 kg/L, so the concentration of the chemical in the water is 0.1 mg/kg.

The BCF = 10³, so the concentration of the chemical in the fish is:

10³ = x / (0.1 mg/kg)

x = 100 mg/kg

For 2 L of water and 30 g of fish:

2 kg × 0.1 mg/kg = 0.2 mg

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The total daily intake is 3.2 mg. Divided by the woman's mass of 50 kg, the dosage is:

(3.2 mg/day) / (50 kg) = 0.064 mg/kg/day

b) The percent from the water is:

0.2 mg / 3.2 mg = 6.25%

And the percent from the fish is:

3 mg / 3.2 mg = 93.75%

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3 years ago

At time t the resultant force on a particle, of mass 250kg is (300ti-400tj)N. Initially, the particle is at the origin and is mo

Harlamova29_29 [7]

Answer:

Explanation:

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2 years ago

Fatigue failure occurs under the condition of (a) High elastic stress (b) High corrosivity (c) High stress fluctuations (d) High

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Answer:

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Explanation:

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3 years ago

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blsea [12.9K]

Answer:

The correct answer is A : Orientation dependence of normal and shear stresses at a point in mechanical members

Explanation:

Since we know that in a general element of any loaded object the normal and shearing stresses vary in the whole body which can be mathematically represented as

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The Mohr circle is graphically displayed in the attached figure.

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2 years ago