Satisfying application of physics

AI Thread Summary
A successful physics lab test involved simulating a bungee jump with an egg payload, achieving the highest grade in the class. The objective was to calculate the correct length of non-elastic string attached to a rubber band to minimize the egg's drop distance to within 3cm of the floor. Using formulas for force and potential energy, the student determined the spring constant and calculated the necessary string length to achieve the desired drop height. The experiment was executed flawlessly, with the egg bouncing back at exactly 3cm. The student also announced their decision to major in physics after meeting with a college adviser.
leftyguitarjo
Messages
52
Reaction score
0
Today, I completed a lab test in my physics test, and received the highest grade in the class. The goal was to simulate a bungee jump. We had to make the payload, an egg in my case, get as close to the floor as possible without touching. To do this, you get a rubber band, and would then calculate a length of non-elastic string to attach to it. Our goal was within 3cm. The catch? you only get one try. I first got a large rubber band, and suspended it from a fixed arm about 2m off the floor. I measured the displacement of the rubber band, and use a force gauge to measure the force. I used those numbers in F=-kx to find the spring constant. I then found the elastic potential energy with Pe=1/2kx^2. I then took the weight of the egg, in Newtons, and calculated the string length with P(elastic)=P(egg) and got .5m. My egg, dropped from the same point that the rubber band was attached to the support, was dropped, and promptly sprang back upon reaching 3cm almost exactly.:approve:Just to sum up my work:
F=kx
9=13.84(.65m)

P(elastic)= 1/2kx^2
2.96= 1/2(13.84).65^2

2.96=mgh

2.96=.6(9.8)h

h=.5m
 
Last edited:
Physics news on Phys.org
Very, very good! That's the kind of physics "lab" that I like.

Zz.
 
ZapperZ said:
Very, very good! That's the kind of physics "lab" that I like.

Zz.

thank you very much.

and BTW, I just met with my college course adviser for the first time today. I am "in", and I'm majoring in physics!
 
leftyguitarjo said:
thank you very much.

and BTW, I just met with my college course adviser for the first time today. I am "in", and I'm majoring in physics!

Great job!

I've had a few similar labs that just *worked* but most of these consist of overcomplicated setups that just manage to work, pure fluke.
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks
I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
Back
Top