Jump to content
Sign in to follow this  
  • entries
  • comments
  • views

Don't Drop The Eggs

Sign in to follow this  


... unless you are instructed to do so by your physics teacher :)

My fellow blogger, zlessard, has also just posted a blog about a similar topic, as we both had to write one up for class. Our mistakes were different but we both had the same goal.

The purpose of this lab was to figure out what height the arm on which the rubber band and egg were attached had to be so the bottom of the egg just touched the top of the paper (resting on a table) below it. To find out what height it needed to be, the potential energy of the system had to be determined. Potential Energy (U)= mass (m)*Acceleration due to gravity(g)*height (h). Once potential energy was found, it would be possible to determine the height, since the mass of the egg was known. To find the potential energy stored different masses were used to determine a different displacement of the rubber band as well as the force applied. On earth we know the acceleration due to gravity is 9.81 m/s^2 so the force applied is easy to find (F=ma). When the different masses were added to the rubber band the displacement was able to be found by measuring how far the rubber band. The area under a force vs. displacement graph is equal to potential energy. This is where my group messed up. Instead of integrating by weight, we integrated by mass. This would give us the wrong value for the potential energy causing the rest of the calculations made to find the height at which to drop the egg from. So after integration, you find the potential energy to be .8932J. Then using the equation U=mgh, you can figure out the height, which in our case would be 1.3007m since our egg had a mass of .07kg and the acceleration due to gravity on earth is 9.81 m/s^2. Yesterday, when we dropped our egg we were lucky enough to make an educated guess that was correct. At least, my group has discovered our mistake (integration... it's important) and can move forward with this knowledge. 

I highly suggest trying this at home (be prepared to clean up and broken eggs!!!) because it's a great lab to do for fun. Even if you do trial and error drops :) 

You'll need a few rubber bands, a place to attach the rubber band to. And then something to attach the rubber band to the egg. Good luck! 

Sign in to follow this  

1 Comment

Recommended Comments

Add a comment...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Terms of Use

The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.

Copyright Notice

APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to info@aplusphysics.com. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.

  • Create New...