Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

The Awesome Egg Drop: Physics Period 9

See title.
by

C W

on 16 February 2012

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of The Awesome Egg Drop: Physics Period 9

Egg Drop: The Awesome Presentation by: BB, TC, CW Physics Period 9 How It Works: The Physics Behind Cushioning - THE EQUATION: Ft=m∆v Change in Momentum:
mass x ∆velocity
(You can't change the mass as it falls, and the velocity depends on the height it drops from.) What You Can't Change Directly: What You Can Change Directly: Impulse: Force x time
( You CAN change the time it takes
to stop!) - SO: The actual impulse and change in momentum
will be the same no matter how we cushion the egg:
we it will be the same mass slowing to zero velocity.

-BUT: By increasing the TIME (t) the egg takes to change its
momentum, we decrease the FORCE (F) on the egg! Less Time to Stop, More Force= SPLAT.

More Time to Stop, Less Force = Success. So: we needed to increase the TIME on impact our egg took to stop moving. Air Resistance What We Did: Applying the Equations To Put it Bluntly: Remember: FORCE is what breaks the egg - the shell can only stand so much force upon impact. Example:
In this Force-Time Graph,
IMPULSE is the area
under the curve! You can decrease this...
(force) By increasing this!
(Time it takes to change velocity) But Wait! There's More: Applying Impulse to
REAL LIFE Collisions Two Ways to Decrease the Force on the Egg:
(and hopefully prevent it from cracking) The "Right" Way: Make it Take More Time to
Change Velocity on Impact Based on the Impulse-Momentum Theorem
Increase Time on impact to decrease force on egg
Icosahedron with suspended egg in center The Loophole-Finding, Far-More-Effective Way:
Use Air resistance to Manipulate Velocity as It Falls - Structure has lots of "give": the straws collapse, and the elastic strings that suspend the egg stretch, so the egg takes more time to stop
- Instead of hitting concrete and stopping instantly - cushioning the egg using the shock-absorbing and shock-distributing structure means less force on the egg as it stops
- The overall impulse/momentum is the same Why an Icosahedron? - 20 triangles
-Triangles = great shock absorbers!
-Distribute force: when the structure
hits the ground, the icosahedron acts
as very good cushioning - it collapses,
extending the time that the egg takes to
stop (Think: bending your knees when
catching an egg) -Gymnasts: bend knees when landing; martial arts people
learn to "fall correctly" - collapsing their body as they fall
-Same idea of "give": by taking more time to change momentum,
the same impulse can apply less force to the body
(Force breaks bones as well as eggs!)

-Cars: airbags slow the time of a body moving in a crash: use of an object with a lot of give to "cushion" the collision
"Crumple zones" - areas made to "crush" upon impact in the car's frame - also use the momentum-impulse theroem to limit force on passengers

-Helmets: acts as an "air bag" for the head, padding slows the time of the head moving, lessens the force on the head - Use of a "parachute" of sorts: four sheets of newspaper, taped to prevent air from flowing through the parachute

- Large amount of surface area catches as much air as possible to slow decsent

- Made of a fairly lightweight material, very thin so not as to have too much mass, and therefore less overall momentum. Ft=m(Vf-Vi) The parachute changes the VELOCITY of the falling egg:
instead of increasing the TIME to decrease FORCE, it lessens the overall momentum and impulse -Bumper Cars: The huge springs and
rubber bumpers also increase the time it
takes for colliding cars to stop, decreasing the
force on the poor children/oversized adults inside

(Because dying is bad in a ride that revolves around
collisions!) Thanks To....
(References from Helpful Sources) Nave, R. (2006, January). Elastic and Inelastic Collisions. Retrieved May 24, 2011, from Georgia State University website:http://hyperphysics.phy-astr.gsu.edu/hbase/hph.html
Pettis, B. (2007, February 5). Egg Drop Strategies. Retrieved May 20, 2011, from Make: Online website: http://blog.makezine.com/archive/2007/02/egg-drop-strategies.html
Tyler, T. (n.d.). Hex-dome. In Straw and String Models. Retrieved May 22, 2011, from Hex-Dome Structures website: http://hexdome.com/models/straws/index.php
Henderson, T. (2011). The Impulse-Momentum Change Theorem: Real-World Applications. Retrieved May 25, 2011, from The Physics Classroom website: http://www.physicsclassroom.com/class/momentum/ u4l1c.cfm
Drag in aerodynamics. (2011, May). Drag (Physics). Retrieved May 25, 2011, from Wikipedia website: http://en.wikipedia.org/wiki/Drag_(physics) Note: the thickly cushioned landing mats add to the effect! THE END
Full transcript