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So I was wondering how you even start this event, in regards to building the machine. I'm pretty lost right now in what to do, and I'm not completely sure how you're even supposed to construct the lever. Any type of help would be appreciated!

https://www.youtube.com/watch?v=qIEbVXtrMT0

Watch this video I found on youtube to kickstart my team's levers. I will say that there are a couple things the person in the video can do better to make better levers, but... It is a good start and intro to the event.

Hope this helps!

Xiangyu

Can someone please help me get started on my lever designs? I’ve made two prototypes, both of which do not work as intended. I am in division C, and my question is do I need counterweights to balance the class 2 or class 3 lever? And also how do I ensure my levers are in equilibrium and will be precise in measuring?
Thanks

You’ll need counterweights if your levers are not in equilibrium. The levers has mass, so depending where you put your fulcrums, the lever will not be balanced.

Thanks, but I’m still unclear on how you would connect the two levers in order to calculate the ratio. Any help?

I used a fishing wire and some glue to connect my class one lever to my class two lever. To calculate my ratios, I like to have a fixed mass on my class one lever. This fixed mass would be the one given by event supervisors for the test. The fixed mass is attached to one of the ends of my class one lever, and the string would be on the other end of the same lever. The distance between the fixed mass and the fulcrum is the same as the distance between the fulcrum and the string.

I attached my string to the class two lever double the length of the distance described above from the fulcrum of the class two lever.

In this setup, you would have to designate the smaller mass as the fixed mass on the class one lever. The larger mass would be slid around on the class two lever until the two levers are parallel to the ground.

With this setup, the ratio of the masses would be equal to the distance between the larger mass to the fulcrum : the distance between the string and the fulcrum on the class two lever.

Sorry, if some of this doesn’t make sense. Ask any questions if you have them. I’m trying to watch the New Year’s countdown.

Thanks so much for your time helping
My question is what do you mean by the string, is that what connects the two levers? And also, you said that the fixed mass to the fulcrum is the same distance as the string to the fulcrum; does that mean that your string can be easily moved to fit this criteria based on where you put the smaller mass?
Thanks again, and if it’s not too much to ask, a diagram maybe would be helpful?
But either way,
Thank you for taking your time to help a fellow builder out.

No problem! I knew I had to clarify some stuff, I would sketch up something when I wake up later. Have a happy New Year’s!

Here is the diagram that I made: https://drive.google.com/open?id=1pWhCe ... D0g57mvneL (edit: this link does not work, I posted a new link further down the thread)

My question is what do you mean by the string, is that what connects the two levers?

Yes, the string/fishing wire is what connects the two levers.

And also, you said that the fixed mass to the fulcrum is the same distance as the string to the fulcrum; does that mean that your string can be easily moved to fit this criteria based on where you put the smaller mass?

The string would be glued down to the lever, so it won't shift during the testing of the lever. That means the fixed mass would be in the same spot whenever you test it.

Also, with this setup, the mass ratios of A:B would be equal to y:x in the diagram in my previous post.