## Hovercraft B/C

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

Justin72835 wrote:
UTF-8 U+6211 U+662F wrote:
Justin72835 wrote:Do you need to know anything about initial and final velocities to solve this question?

Whoops: They are moving toward each other, the ball with a speed of 5 m/s and the pencil with a speed of 0.4 m/s.

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:Yep, your turn! Wolfram alpha link to the series of equations if anyone wants it: Link

Awesome

An amusement park is planning on constructing a new ride and needs help with all the planning. The track begins at a height of 60 meters and slopes downward at a constant angle. The coefficient of rolling friction for the wheels of the roller coaster is 0.05. If the park wants the ride to have a final velocity of at least 25 m/s at its lowest point, what should the minimum angle of slope be?
Last edited by Justin72835 on March 15th, 2018, 4:55 pm, edited 1 time in total.
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Seven Lakes High School '19

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

Justin72835 wrote:An amusement park is planning on constructing a new ride and needs help with all the planning. The track begins at a height of 60 meters and slopes downward at a constant angle. The coefficient of rolling friction for the wheels of the roller coaster is 0.05. If the park wants the ride to have a final velocity of at least 25 m/s at its lowest point, what should the minimum angle of slope be?

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:
Justin72835 wrote:An amusement park is planning on constructing a new ride and needs help with all the planning. The track begins at a height of 60 meters and slopes downward at a constant angle. The coefficient of rolling friction for the wheels of the roller coaster is 0.05. If the park wants the ride to have a final velocity of at least 25 m/s at its lowest point, what should the minimum angle of slope be?

Correct! You're next!
"The fault, dear Brutus, is not in our stars,
But in ourselves, that we are underlings."

Seven Lakes High School '19

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### Re: Hovercraft B/C

A 1 kg hovercraft is plugged into a power source with a 14 m long wire. It floats 2 cm off the ground and goes around in a circle around the power source at 6 m/s. The fans the hovercraft uses "convert" 1 Joule of energy into 1 Newton of force every second. Find the wattage of the power source.

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:A 1 kg hovercraft is plugged into a power source with a 14 m long wire. It floats 2 cm off the ground and goes around in a circle around the power source at 6 m/s. The fans the hovercraft uses "convert" 1 Joule of energy into 1 Newton of force every second. Find the wattage of the power source.

"The fault, dear Brutus, is not in our stars,
But in ourselves, that we are underlings."

Seven Lakes High School '19

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### Re: Hovercraft B/C

Justin72835 wrote:
UTF-8 U+6211 U+662F wrote:A 1 kg hovercraft is plugged into a power source with a 14 m long wire. It floats 2 cm off the ground and goes around in a circle around the power source at 6 m/s. The fans the hovercraft uses "convert" 1 Joule of energy into 1 Newton of force every second. Find the wattage of the power source.

Not quite

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:
Not quite

Take 2.0
"The fault, dear Brutus, is not in our stars,
But in ourselves, that we are underlings."

Seven Lakes High School '19

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### Re: Hovercraft B/C

Justin72835 wrote:
UTF-8 U+6211 U+662F wrote:
Not quite

Take 2.0

Almost

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:
Justin72835 wrote:
UTF-8 U+6211 U+662F wrote:
Not quite

Take 2.0

Almost

Final effort
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But in ourselves, that we are underlings."

Seven Lakes High School '19

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

Justin72835 wrote:
UTF-8 U+6211 U+662F wrote:
Justin72835 wrote:
Take 2.0

Almost

Final effort

Yep Of course, it would be more if I remembered to specify a coefficient of friction

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:Yep Of course, it would be more if I remembered to specify a coefficient of friction

A uniform 0.4 m long stick rotates freely about a horizontal axis through one of its ends. It is released at an unknown angle to the vertical. When it hangs straight down, the speed of the tip of the stick is 3.5 m/s. How large is the unknown angle?
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But in ourselves, that we are underlings."

Seven Lakes High School '19

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### Re: Hovercraft B/C

Justin72835 wrote:A uniform 0.4 m long stick rotates freely about a horizontal axis through one of its ends. It is released at an unknown angle to the vertical. When it hangs straight down, the speed of the tip of the stick is 3.5 m/s. How large is the unknown angle?

Kind of confused here. Might be asking too much, but could you draw a picture?

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### Re: Hovercraft B/C

UTF-8 U+6211 U+662F wrote:
Justin72835 wrote:A uniform 0.4 m long stick rotates freely about a horizontal axis through one of its ends. It is released at an unknown angle to the vertical. When it hangs straight down, the speed of the tip of the stick is 3.5 m/s. How large is the unknown angle?

Kind of confused here. Might be asking too much, but could you draw a picture?

I think this picture shows what he's talking about:

The rod rotates in the plane of the page
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UTF-8 U+6211 U+662F
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Ohh, I see.