## Simple Machines B/Compound Machines C

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

So...

Can I ask a question?

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

So...

Can I ask a question?

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

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

So...

Can I ask a question?

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`

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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 2202 times

jkang
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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
`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

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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