## Simple Machines B/Compound Machines C

FenderBender87
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### Re: Simple Machines B/Compound Machines C

How would you instal the sliding hook? And by the way thanks SO much Schlopedia

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

Can someone explain to me the ideal mechanical advantage of pulleys? Some sources say that it is the number of pulleys, others say the number of strings, and others say its one for a stationary and 2 for a moving. I feel like this shouldn't be this complicated so if someone could explain it to me I would be very grateful.

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

How would you instal the sliding hook? And by the way thanks SO much Schlopedia
Find something that slips over the bar of your scale and glue/attach a hook to it. We dug around in the toy box and found a tube of some sort (I thought it was a plastic Tinker Toy piece but a quick Google search doesn't show it...) that worked just fine.
Homeschool Science Colorado since August 2008

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

Can someone explain to me the ideal mechanical advantage of pulleys? Some sources say that it is the number of pulleys, others say the number of strings, and others say its one for a stationary and 2 for a moving. I feel like this shouldn't be this complicated so if someone could explain it to me I would be very grateful.
For block and tackle systems, count the lines that are directly connected to the mass.

A stationary pulley only changes the direction of the pull. No mechanical advantage there.

A moving pulley gives mechanical advantage: you use less force but must pull the rope more. Youtube has some good videos and there are lots of websites and worksheets out there for practice.
Homeschool Science Colorado since August 2008

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

Thanks! One more question, for the lever, it says it must fit in a box 100x100x50 at impound, but does it have to actually be in a box? Or does it just have to theoretically fit?

Thanks again for everyone's help!!!

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

Thanks! One more question, for the lever, it says it must fit in a box 100x100x50 at impound, but does it have to actually be in a box? Or does it just have to theoretically fit?

Thanks again for everyone's help!!!
No. Many science olympiad events give max sizes for devices based upon a theoretical box size. You don't have to have any actual box though.

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

Thanks! One more question, for the lever, it says it must fit in a box 100x100x50 at impound, but does it have to actually be in a box? Or does it just have to theoretically fit?

Thanks again for everyone's help!!!
No. Many science olympiad events give max sizes for devices based upon a theoretical box size. You don't have to have any actual box though.
So if we bring it there in a box in two pieces, can we set it up at the impound? Or if not, can we set it up at the competition without it counting as are "part 2" time?

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

Thanks! One more question, for the lever, it says it must fit in a box 100x100x50 at impound, but does it have to actually be in a box? Or does it just have to theoretically fit?

Thanks again for everyone's help!!!
No. Many science olympiad events give max sizes for devices based upon a theoretical box size. You don't have to have any actual box though.
So if we bring it there in a box in two pieces, can we set it up at the impound? Or if not, can we set it up at the competition without it counting as are "part 2" time?
I'd set it up at impound or before. I'd recommend having it ready to run before your competition time.
Homeschool Science Colorado since August 2008

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

U dont have to. My partner and I don't bring a box and we've been fine.

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

Can someone explain to me the ideal mechanical advantage of pulleys? Some sources say that it is the number of pulleys, others say the number of strings, and others say its one for a stationary and 2 for a moving. I feel like this shouldn't be this complicated so if someone could explain it to me I would be very grateful.

The IMA of a pulley system is equal to the number of rope that LIFT the load.