## Hovercraft B/C

photolithoautotroph
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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:
Tesel wrote:Consider a pipe with radius r.

If an ideal fluid is flowing through the pipe, how would the flow rate change if the radius was increased to 2r?

If a non-ideal, viscous fluid is flowing through the pipe, how would the flow rate change if the radius was increased to 2r?

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Tesel
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### Re: Hovercraft B/C

photolithoautotroph wrote:
UTF-8 U+6211 U+662F wrote:
Tesel wrote:Consider a pipe with radius r.

If an ideal fluid is flowing through the pipe, how would the flow rate change if the radius was increased to 2r?

If a non-ideal, viscous fluid is flowing through the pipe, how would the flow rate change if the radius was increased to 2r?

I should have clarified the question a lot better.
But yes, you made the right assumptions, and that was the correct use of Poiseuille's Law. Correct!

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### Re: Hovercraft B/C

photolithoautotroph wrote:
UTF-8 U+6211 U+662F wrote:
Tesel wrote:Consider a pipe with radius r.

If an ideal fluid is flowing through the pipe, how would the flow rate change if the radius was increased to 2r?

If a non-ideal, viscous fluid is flowing through the pipe, how would the flow rate change if the radius was increased to 2r?

photolithoautotroph
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### Re: Hovercraft B/C

If nobody posts a question in this long, you can.
Question
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IvanGe
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### Re: Hovercraft B/C

photolithoautotroph wrote:If nobody posts a question in this long, you can.
Question

a = m1g - m2g / m1+ m2
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### Re: Hovercraft B/C

photolithoautotroph wrote:If nobody posts a question in this long, you can.
Question

EDIT: Whoops, didn't see other answer

PW240.3
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### Re: Hovercraft B/C

photolithoautotroph wrote:If nobody posts a question in this long, you can.
Question

Since you have to account for the pulley's moment of inertia, wouldn't the a be a=(m1-m2)g/(m1+m2+M/4)

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### Re: Hovercraft B/C

I'm just going to ask a question because no one's verified the answer.

With what constant velocity can a 4.00 hp motor raise a mass of 125 kg?
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### Re: Hovercraft B/C

IvanGe wrote:I'm just going to ask a question because no one's verified the answer.

With what constant velocity can a 4.00 hp motor raise a mass of 125 kg?

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IvanGe
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### Re: Hovercraft B/C

IvanGe wrote:I'm just going to ask a question because no one's verified the answer.

With what constant velocity can a 4.00 hp motor raise a mass of 125 kg?

that's what i got, but the answer key said 2.76 m/s?

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### Re: Hovercraft B/C

IvanGe wrote:I'm just going to ask a question because no one's verified the answer.

With what constant velocity can a 4.00 hp motor raise a mass of 125 kg?

Can you explain this one

Tesel
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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:
IvanGe wrote:I'm just going to ask a question because no one's verified the answer.

With what constant velocity can a 4.00 hp motor raise a mass of 125 kg?

Can you explain this one

So the first thing to understand is that hp is a unit of power, just not an SI unit. 1 hp = 745.7 W.
From here, we can use this relationship P = Fv to solve the equation.
$4.00 hp * 745.7 W/1 hp = 125 kg * 9.81 m/s^2 * v$

The reason this works is that power is really a unit of energy per time. Energy, meanwhile, is a unit of force over a distance. So, power is a unit of force over a distance per time; the distance per time corresponds to velocity.

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### Re: Hovercraft B/C

Tesel wrote:
UTF-8 U+6211 U+662F wrote:

Can you explain this one

So the first thing to understand is that hp is a unit of power, just not an SI unit. 1 hp = 745.7 W.
From here, we can use this relationship P = Fv to solve the equation.
$4.00 hp * 745.7 W/1 hp = 125 kg * 9.81 m/s^2 * v$

The reason this works is that power is really a unit of energy per time. Energy, meanwhile, is a unit of force over a distance. So, power is a unit of force over a distance per time; the distance per time corresponds to velocity.

Ah, I see. Thanks!

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### Re: Hovercraft B/C

IvanGe wrote:
IvanGe wrote:I'm just going to ask a question because no one's verified the answer.

With what constant velocity can a 4.00 hp motor raise a mass of 125 kg?

that's what i got, but the answer key said 2.76 m/s?

Suppose I have a bowling ball with a diameter of 25 centimeters. What is the largest mass it can have such that it floats in corn syrup (specific gravity = 1.4)?
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### Re: Hovercraft B/C

Adi1008 wrote:Suppose I have a bowling ball with a diameter of 25 centimeters. What is the largest mass it can have such that it floats in corn syrup (specific gravity = 1.4)?