Simple Machines B/Compound Machines C

slytherin
Member
Member
Posts: 70
Joined: October 1st, 2012, 5:56 pm
Division: B
State: KS
Contact:

Re: Simple Machines B/Compound Machines C

Postby slytherin » March 14th, 2015, 9:20 am

davidkim2106 wrote:OH!!! So what kinds of hooks would they be? Pictures would be awesome. Also, our lever doesn't seem to work, we use the right equation, but when we hang them directly (and then connect the two levers together with a string), our ratios are always off for some reason.

Any ideas? Thanks guys

Our team connected 2 zipties around the lever and then added a wire-like thing (that's not really like wire, but can bend and is strong, sorry for the REALLY bad explanation of what it is..) to the bottom of the ziptie so that it closed around the ziptie on one end and had a little U on the other end for you to hook the mass on.
State:
Anatomy: 2nd
Meteorology: 2nd
Simple Machines: 2nd
Solar System: 2nd
Notice a pattern :lol:

User avatar
samlan16
Member
Member
Posts: 519
Joined: December 30th, 2013, 2:54 pm
Division: Grad
State: TN
Contact:

Re: Simple Machines B/Compound Machines C

Postby samlan16 » March 14th, 2015, 11:24 am

GoldenKnight1 wrote:
jayrey wrote:I found it after I posted. Thanks so much!! On another note, can we have our apparatus setup at the edge of the table so that the mass hanging down from the second class lever is hanging below the Lowest edge of the apparatus?


Though let me play the role of the mean event supervisor: Does your device work without the table? If not, did you impound the table? What if the supervisor is having you do this on the floor?

Just better to do what bernard suggested and elevate your fulcrum.

You could alternatively make your lever arm shorter if possible. That way, you are less likely to hit the table.
Remember, we are proud of every team that participated and you are all winners.

joeyjoejoe
Member
Member
Posts: 142
Joined: December 27th, 2012, 12:56 pm
Division: C
State: GA
Contact:

Re: Simple Machines B/Compound Machines C

Postby joeyjoejoe » March 14th, 2015, 11:51 am

jayrey wrote:On another note, can we have our apparatus setup at the edge of the table so that the mass hanging down from the second class lever is hanging below the Lowest edge of the apparatus?


You could also prevent it from going down that far by putting some sort of stop on the lever. We implemented ours in the form of two nails 1" above and below the right side of our class 1 lever. That way, the lever couldn't go above or below balanced position by more than a few inches. This did create the need for a "quicker eye" when adjusting the lever but we came up with a solution for that as well - which I will share after all competitions are over. ;)

User avatar
davidkim2106
Member
Member
Posts: 8
Joined: February 10th, 2012, 4:27 pm
Division: C
State: AL
Location: Montgomery, AL
Contact:

Re: Simple Machines B/Compound Machines C

Postby davidkim2106 » March 14th, 2015, 8:14 pm

Anyone have any pictures of their device?
Sup.

User avatar
boomvroomshroom
Member
Member
Posts: 189
Joined: February 19th, 2015, 5:10 pm
Division: C
State: CA
Contact:

Re: Simple Machines B/Compound Machines C

Postby boomvroomshroom » March 14th, 2015, 8:17 pm

davidkim2106 wrote:Anyone have any pictures of their device?


You could go in the image gallery.

User avatar
bernard
Administrator
Administrator
Posts: 1889
Joined: January 5th, 2014, 3:12 pm
Division: Grad
State: WA
Location: Seattle, WA
Contact:

Re: Simple Machines B/Compound Machines C

Postby bernard » March 15th, 2015, 9:41 am

davidkim2106 wrote:Anyone have any pictures of their device?

A link to a picture of the device I made for our team.
"One of the ways that I believe people express their appreciation to the rest of humanity is to make something wonderful and put it out there."

User avatar
davidkim2106
Member
Member
Posts: 8
Joined: February 10th, 2012, 4:27 pm
Division: C
State: AL
Location: Montgomery, AL
Contact:

Re: Simple Machines B/Compound Machines C

Postby davidkim2106 » March 15th, 2015, 10:39 am

boomvroomshroom wrote:
davidkim2106 wrote:Anyone have any pictures of their device?


You could go in the image gallery.


Keep in mind I said pictures of their devices :)

bernard wrote:
davidkim2106 wrote:Anyone have any pictures of their device?

A link to a picture of the device I made for our team.


Thanks bernard :) Could you explain what the little things above the levers are? Also, where would you attach the masses? I don't see hooks

EDIT: nvm i see them, thanks :)
Sup.

User avatar
chinesesushi
Member
Member
Posts: 258
Joined: September 17th, 2013, 4:57 pm
Division: C
State: CA
Contact:

Re: Simple Machines B/Compound Machines C

Postby chinesesushi » March 15th, 2015, 10:52 am

bernard wrote:
davidkim2106 wrote:Anyone have any pictures of their device?

A link to a picture of the device I made for our team.


Thanks bernard :) Could you explain what the little things above the levers are? Also, where would you attach the masses? I don't see hooks

EDIT: nvm i see them, thanks :)


I believe those are levels that he uses to see whether the system of levers is in equilibrium or not, for more accuracy.
Never argue with an idiot, they will drag you down to their level and then beat you with experience.
Before you criticize a man, walk a mile in his shoes. That way you'll be a mile away and he'll be shoeless.
You should only create problems, that only you know solutions to.

goodcheer
Member
Member
Posts: 150
Joined: October 27th, 2012, 7:09 am
Division: B
State: KY
Contact:

Re: Simple Machines B/Compound Machines C

Postby goodcheer » March 18th, 2015, 6:26 am

bernard wrote:
davidkim2106 wrote:Anyone have any pictures of their device?

A link to a picture of the device I made for our team.



Bernard, I understand how the first class lever can rest in equilibrium, but how about the second class lever? Do you have a fixed counter-weight attached to it to the right of the fulcrum or do you adjust the first class lever to the point where it can balance the second class lever? Anyone else with idea please help. We just got someone new on this event. Thanks.

User avatar
bernard
Administrator
Administrator
Posts: 1889
Joined: January 5th, 2014, 3:12 pm
Division: Grad
State: WA
Location: Seattle, WA
Contact:

Re: Simple Machines B/Compound Machines C

Postby bernard » March 18th, 2015, 7:45 am

goodcheer wrote:
bernard wrote:
davidkim2106 wrote:Anyone have any pictures of their device?

A link to a picture of the device I made for our team.



Bernard, I understand how the first class lever can rest in equilibrium, but how about the second class lever? Do you have a fixed counter-weight attached to it to the right of the fulcrum or do you adjust the first class lever to the point where it can balance the second class lever? Anyone else with idea please help. We just got someone new on this event. Thanks.

Yes, a fixed counterweight would let the second class lever rest in equilibrium, which would hopefully allow for more accurate predictions.
"One of the ways that I believe people express their appreciation to the rest of humanity is to make something wonderful and put it out there."

User avatar
UTF-8 U+6211 U+662F
Exalted Member
Exalted Member
Posts: 1084
Joined: January 18th, 2015, 7:42 am
Division: C
State: PA
Location: (0, 0)
Contact:

Re: Simple Machines B/Compound Machines C

Postby UTF-8 U+6211 U+662F » March 18th, 2015, 6:22 pm

So... Apparently, there was a conflict, and now, I'm doing Simple Machines. What kinds of things should I do for simple machine concepts and terminology?

chalker
Member
Member
Posts: 2066
Joined: January 9th, 2009, 7:30 pm
Division: Grad
State: OH
Contact:

Re: Simple Machines B/Compound Machines C

Postby chalker » March 18th, 2015, 7:57 pm

bernard wrote:Yes, a fixed counterweight would let the second class lever rest in equilibrium, which would hopefully allow for more accurate predictions.


But then it might not be considered a true 2nd class lever anymore... more like a hybrid 1st/2nd class lever....

Student Alumni
National Event Supervisor
National Physical Sciences Rules Committee Chair

User avatar
bernard
Administrator
Administrator
Posts: 1889
Joined: January 5th, 2014, 3:12 pm
Division: Grad
State: WA
Location: Seattle, WA
Contact:

Re: Simple Machines B/Compound Machines C

Postby bernard » March 18th, 2015, 9:50 pm

chalker wrote:
bernard wrote:Yes, a fixed counterweight would let the second class lever rest in equilibrium, which would hopefully allow for more accurate predictions.


But then it might not be considered a true 2nd class lever anymore... more like a hybrid 1st/2nd class lever....

By the FAQ that states the the 40cm of the class 2 lever is just the distance between the fulcrum and effort points, could I call an 80cm beam a class 2 lever if the load and effort are on the same side of the fulcrum? I suppose the picture of our device I posted a while ago could be considered a hybrid since there is 5cm of meterstick opposite to the 40cm class 2 lever.
"One of the ways that I believe people express their appreciation to the rest of humanity is to make something wonderful and put it out there."

joeyjoejoe
Member
Member
Posts: 142
Joined: December 27th, 2012, 12:56 pm
Division: C
State: GA
Contact:

Re: Simple Machines B/Compound Machines C

Postby joeyjoejoe » March 19th, 2015, 4:35 am

Even with that definition, I would consider the class 2 lever actually a class 1 lever. It never even crossed our minds to build ours that way. Placing a counterbalance on a class 1 lever doesn't change its type but doing so with a class 2 arguably does.

chalker
Member
Member
Posts: 2066
Joined: January 9th, 2009, 7:30 pm
Division: Grad
State: OH
Contact:

Re: Simple Machines B/Compound Machines C

Postby chalker » March 19th, 2015, 10:13 am

bernard wrote:By the FAQ that states the the 40cm of the class 2 lever is just the distance between the fulcrum and effort points, could I call an 80cm beam a class 2 lever if the load and effort are on the same side of the fulcrum? I suppose the picture of our device I posted a while ago could be considered a hybrid since there is 5cm of meterstick opposite to the 40cm class 2 lever.


As always, this isn't the place for official clarifications / comments.... Note that the purpose of that FAQ was to make it easier for people to construct the levers. It's REALLY hard to come up with a design that has the fulcrum exactly at the edge of the beam for example. Having a little bit of extra material overhanging the fulcrum doesn't significantly impact the functionality of the lever.

Student Alumni
National Event Supervisor
National Physical Sciences Rules Committee Chair


Return to “2015 Lab Events”

Who is online

Users browsing this forum: No registered users and 1 guest