## Simple Machines B/Compound Machines C

UTF-8 U+6211 U+662F
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### Re: Simple Machines B/Compound Machines C

So...

A car has a motor which rotates a _________ (simple machine). How efficient is this? (Guesstimate)

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### Re: Simple Machines B/Compound Machines C

70%
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### Re: Simple Machines B/Compound Machines C

UTF-8 U+6211 U+662F wrote:So...

A car has a motor which rotates a _________ (simple machine). How efficient is this? (Guesstimate)
wheel and axle, 99%?
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### Re: Simple Machines B/Compound Machines C

Unome wrote:
[math](10 m)(20/25*20 kg) + (15 m)(x kg) = (5 m)(15 kg) + (2.5 m)(4 kg)[/math]
[math]x=5kg[/math]
Definitely negative
Correct.

So I posted the question, then realized I would need the answers too, and then realized it was negative.
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UTF-8 U+6211 U+662F
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### Re: Simple Machines B/Compound Machines C

jkang wrote:
UTF-8 U+6211 U+662F wrote:So...

A car has a motor which rotates a _________ (simple machine). How efficient is this? (Guesstimate)
wheel and axle, 99%?
Correct except I was asking how the motor was which is probably more in
30%-40% zone

UTF-8 U+6211 U+662F
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### Re: Simple Machines B/Compound Machines C

So, assume this is an ideal simple machine.

What type of machine is this? What is the IMA? Find x. Find the torque generated.
Untitled1.png (4.47 KiB) Viewed 2578 times

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### Re: Simple Machines B/Compound Machines C

UTF-8 U+6211 U+662F wrote:So, assume this is an ideal simple machine.

What type of machine is this? What is the IMA? Find x. Find the torque generated.
Untitled1.png
Uh probs a wheel and axle, can't really tell cuz MS Paint is pt cringe. Assuming that x is input, the IMA is 2.5. x = 32 N, and the torque generated (assuming only by x) is 320 Nm.
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### Re: Simple Machines B/Compound Machines C

jkang wrote:
UTF-8 U+6211 U+662F wrote:So, assume this is an ideal simple machine.

What type of machine is this? What is the IMA? Find x. Find the torque generated.
Untitled1.png
Uh probs a wheel and axle, can't really tell cuz MS Paint is pt cringe. Assuming that x is input, the IMA is 2.5. x = 32 N, and the torque generated (assuming only by x) is 320 Nm.
Yes, it is a wheel and axle. The IMA is equal to 10m/8cm, which is 250. Therefore, the IMA is 250. x = 0 N (the arrows are facing perpendicular directions) and therefore, the torque is 0 Nm.

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