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4 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]4 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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THE MASS FOR OBJECT 1 is 107.01 grams what is the objects force in Newton’s answer please

Aleksandr [31]

Given that,

Mass of the object 1, m = 107.01 grams

To find,

Force on the object.

Solution,

The force acting on the object is gravitational force. The force is given by the formula as follow :

F = mg

g is acceleration due to gravity

F = 0.10701 kg × 9.8 m/s²

F = 1.048 N

So, the force acting on object 1 is 1.048 N.

5 0

3 years ago

A ball is dropped from rest from the top of a cliff that is 30 m high. From ground

trasher [3.6K]

The distance below the top of the cliff that the two balls cross paths is 7.53 meters.

<u>Given the following data:</u>

Initial velocity = 0 m/s (since the ball is dropped from rest).

Height = 30 meters.

<u>Scientific data:</u>

Acceleration due to gravity (a) = 9.8 $m/s^2$ .

To determine how far (distance) below the top of the cliff that the two balls cross paths, we would apply the third equation of motion.

<h3>How to calculate the velocity.</h3>

Mathematically, the third equation of motion is given by this formula:

$V^2 = U^2 +2aS$

<u>Where:</u>

V is the final velocity.

U is the initial velocity.

a is the acceleration.

S is the distance covered.

Substituting the parameters into the formula, we have;

$V^2 = 0^2 +2(9.8) \times 30\\\\V^2 = 588\\\\V=\sqrt{588}$

V = 24.25 m/s.

<u>Note:</u> The final velocity of the first ball becomes the initial velocity of the second ball.

The time at which the two balls meet is calculated as:

$Time = \frac{S}{U} \\\\Time = \frac{30}{24.25}$

Time = 1.24 seconds.

The position of the ball when it is dropped from the cliff is calculated as:

$y_1 = h-\frac{1}{2} at^2\\\\y_1 = 30-\frac{1}{2} \times 9.8 \times 1.24^2\\\\y_1 = 30-7.53\\\\y_1=22.47\;meters$

Lastly, the distance below the top of the cliff is calculated as:

$Distance = 30-22.47$

Distance = 7.53 meters.

Read more on distance here: brainly.com/question/10545161

4 0

3 years ago

Within a cubic unit cell, sketch the directions of [012], [721], [110].

exis [7]

Answer:

[012] :

Here x component is zero. That is why this is in y- z plane

[721] :

This is in all three plane .It means it is in space.

[110] :

Here z component is zero.

That is why this is in x -y plane

From the cubic unit directions we can easily understand all given directions [012], [721], [110].

7 0

3 years ago

A company, studying the relation between job satisfaction and length of service of employees, classified employees into three le

Wewaii [24]

Answer:

Below see details

Explanation:

A) It is attached. Please see the picture

B) First to calculate the overall mean,

μ=65∗25/75+80∗25/75+95∗25/75

μ=65∗25/75+80∗25/75+95∗25/75 = 80

Next to calculate E(MSTR) = σ2+(1/r−1) ∑ni(μi−μ)^2 = 5634

And E(MSE) = σ^2= 9

C) Yes, it is substantially large than E(MSE) in this case.

D) If we sampled 25 employees from each group, we are likely to get a F statistics to indicate differences of job satisfactions among three types of length of service of employees.

3 0

3 years ago

If the gear ratio is 3:5 does it increase torque or speed?

Bas_tet [7]

Answer:

yes it does

Explanation:

3 0

3 years ago

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