## Hovercraft B/C

UTF-8 U+6211 U+662F
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### Re: Hovercraft B/C

Riptide wrote:
UTF-8 U+6211 U+662F wrote:What is an integrated hovercraft?

Wasn't too sure on what this could be but it looks like it is a hovercraft in which "only one propeller is used to provide both lift and thrust air". These questions however are no longer a part of hovercraft (fortunately) so no point to really learn these facts or add them to your binder (although questions like these have showed up in an invitational for me earlier this year).

Oh whoops, I could've sworn the test section didn't change. Oh well, that's right. Your turn!

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### Re: Hovercraft B/C

A circle rotates clockwise at 100 rpm and has a constant counterclockwise acceleration of 4 rad/s^2 for 5.5 seconds. What is the angular displacement?
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Justin72835
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### Re: Hovercraft B/C

Riptide wrote:A circle rotates clockwise at 100 rpm and has a constant counterclockwise acceleration of 4 rad/s^2 for 5.5 seconds. What is the angular displacement?

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### Re: Hovercraft B/C

Justin72835 wrote:
Riptide wrote:A circle rotates clockwise at 100 rpm and has a constant counterclockwise acceleration of 4 rad/s^2 for 5.5 seconds. What is the angular displacement?

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### Re: Hovercraft B/C

Are we allowed do put Lego wheels on the sides of our hovercraft to help the hovercraft roll against the sides ?

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### Re: Hovercraft B/C

mattruff wrote:Are we allowed do put Lego wheels on the sides of our hovercraft to help the hovercraft roll against the sides ?

Sounds like an interesting idea . Not too sure if it’d be allowed but try asking on the actual hover forum I’m sure some discussion will spur on it.
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### Re: Hovercraft B/C

Riptide wrote:
Justin72835 wrote:
Riptide wrote:A circle rotates clockwise at 100 rpm and has a constant counterclockwise acceleration of 4 rad/s^2 for 5.5 seconds. What is the angular displacement?

A hammer with mass m is dropped from rest from a height h above the earth's surface. This height is not necessarily small compared with the radius Re of the earth. If you ignore air resistance, derive an expression for the speed v of the hammer when it reaches the surface of the earth. Your expression should involve h, Re, and me, the mass of the earth.
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### Re: Hovercraft B/C

Justin72835 wrote:
Riptide wrote:
Justin72835 wrote:

A hammer with mass m is dropped from rest from a height h above the earth's surface. This height is not necessarily small compared with the radius Re of the earth. If you ignore air resistance, derive an expression for the speed v of the hammer when it reaches the surface of the earth. Your expression should involve h, Re, and me, the mass of the earth.

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Justin72835
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### Re: Hovercraft B/C

Good job; I guess it's your turn now!
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### Re: Hovercraft B/C

Justin72835 wrote:

Good job; I guess it's your turn now!

A uniform stick of length $L$ is fixed at one end and is free to rotate in the plane of the computer screen. It is initially released at an angle $\theta$ to the vertical. When the stick has fallen to the point where it hangs straight down, the speed at the tip is $v$ . What is $\theta$ ?
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### Re: Hovercraft B/C

Adi1008 wrote:A uniform stick of length $L$ is fixed at one end and is free to rotate in the plane of the computer screen. It is initially released at an angle $\theta$ to the vertical. When the stick has fallen to the point where it hangs straight down, the speed at the tip is $v$ . What is $\theta$ ?

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### Re: Hovercraft B/C

Riptide wrote:
Adi1008 wrote:A uniform stick of length $L$ is fixed at one end and is free to rotate in the plane of the computer screen. It is initially released at an angle $\theta$ to the vertical. When the stick has fallen to the point where it hangs straight down, the speed at the tip is $v$ . What is $\theta$ ?

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Seven Lakes High School '18
Beckendorff Junior High '14

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### Re: Hovercraft B/C

A 8 gram bullet is fired horizontally with a speed of 400 m/s into a 1.2 kg block of wood at rest on the floor. If the coefficient of friction between the block and the table is 0.2, A) how far will the block slide and B) what fraction of the bullet's energy is dissipated in the collision itself?
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### Re: Hovercraft B/C

Riptide wrote:A 8 gram bullet is fired horizontally with a speed of 400 m/s into a 1.2 kg block of wood at rest on the floor. If the coefficient of friction between the block and the table is 0.2, A) how far will the block slide and B) what fraction of the bullet's energy is dissipated in the collision itself?

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Sounds of Music: -/-
Thermodynamics: 3/-

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### Re: Hovercraft B/C

Justin72835 wrote:
Riptide wrote:A 8 gram bullet is fired horizontally with a speed of 400 m/s into a 1.2 kg block of wood at rest on the floor. If the coefficient of friction between the block and the table is 0.2, A) how far will the block slide and B) what fraction of the bullet's energy is dissipated in the collision itself?