Preparing to teach Benny's Lego League team about levers, I realized that I myself knew nothing about levers. I vaguely recalled that a crowbar is one, and that force times distance equals knit one purl two Francis Bacon. Beyond that, I was in the dark. When I was 18, I took a class called University Physics, where these things were probably discussed. OR maybe not. The people in my class may have all been well beyond the study of simple machines. Maybe I was too, at the time.
What I chiefly remember about
University Physics was that I was in the middle of trying to get my
school to boycott table grapes and thereby save the world from injustice. I'm pretty sure I missed a few labs and maybe even the final. I got an A the first semester, a B the second semester, and from there things got really bad and I ended up an English major. I'm sure my
physics professor wanted to crack my head like a nut on several occasions. I was a terrible student. Really terrible in an epic, timeless way. Rotten. At the time, calculus was giving me hives.
Anyway, now that I have two bright young students on my roster and am no longer so completely absorbed in electric guitars and oppressed peoples, I went to the library and learned about levers. And, because I am me, I wrote a song about it to teach this info to the children.
Here is a link to a PDF of the song sheet lyrics:
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Here are the lyrics:
LEVER LA LA LA
In a first class lever, the fulcrum is between
The force and the mighty load
Which might be water or a kid named Jean
You use a first class lever to paddle a canoe
A seesaw or a scissors or the
Shoehorn in your shoe
Chorus:
LA LA LEVER
La-la-la-la-la-LEVER
Your load is so heavy and your fulcrum is fixed
But LA LA LEVER
La-la-la-la-la-LEVER
If I apply some force today
We can lever all your troubles away
That's not all the levers we've got
Let's give the second class lever a shot
In a second class lever the force is at one end
The fulcrum's at the other end
The load is in the middle but the bar won't bend
A door is a second class lever, and a wheelbarrow's one too
If you like to use a nutcracker
Try lever number two!
Chorus
That's not all the levers we've got
Let's give the third class lever a shot
In a third class lever it's the fulcrum, then the force
Then the load on the other side
Which might be an apple or a stick or a horse
Your arms are third class levers, your legs are levers too
And shovels, slings, and spoons
When you use them to fling food.
Chorus
And here is a video of the Legodiles (plus one extra little brother) singing the lever song:
Here's my chance to publicly apologize to Dr. Fulcher for being a rotten student. Homeschooling a seven-year-old is a perfect chance to start over on physics, and this time I'm paying attention.
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