SPECTRA: Demo ideas by https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm Post ideas for demos or comment on others en-us 2023-01-06 17:15:45 UTC 2025-10-25 21:49:31 UTC hello@padlet.com Fiber optics demo fbonettamisteli https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2435890931 Demo: 
You have graduated cylinders full of water with a little bit of milk/intralipid for scatter. You take a laser pointer and angle it at the bottom of the tube and you will observe total internal reflection in the tube if the angle is correct. This is how fiber optics work. 
Then we can show optical fibers and demonstrate how they carry light.

I have used this activity before with middle/high school students. It is a lesson on how fiber optics work, which we can easily tie into applications like diffuse optical tomography or photoacoustics or spectroscopy. 

]]> 2023-01-06 17:30:56 UTC https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2435890931 Strawberry DNA isolation https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2435937290 We would need: ziplocs, strawberries (fresh or frozen), dish detergent, water, plastic cups, coffee filters, cold rubbing alcohol, salt, measuring cups and spoons, and some coffee stirrers. 

1. Remove leaves from strawberries
2. Put berries in a plastic bag and smash it for two minutes
3. Mix detergent, salt, and water to make DNA extraction liquid. 
4. Put DNA extraction liquid into the bag of strawberries and smash for another minute. 
5. Pour the bag contets into a coffee filter inside a plastic cup and filter.
6. Add rubbing alcohol to the filtered liquid, DNA will rise to the top. You can use the coffee stirrer to play with your DNA :D

I have done this activity with the girl scouts before Age 6-12 and it's a fun and easy activity for everyone!]]> 2023-01-06 18:23:36 UTC https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2435937290 Laser Microscope Made With a Drop of Water https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2436186523 a laser pointer is shone through a drop of water collected from the base of a potted plant (or pond water) and the magnified image could be seen in the distant view dot of a laser pointer's beam.
The drop of water was pushed out of a syringe to the point just before the surface tension gave way to falling water. The drop of water acts as a small spherical lens and as the light beam passes through, refraction causes a magnified image to appear on the wall beyond. The shadows of microbial life dotting around the wall can clearly be seen dancing and feeding.
 
]]> 2023-01-07 03:54:34 UTC https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2436186523 Identify objects with light https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2436940950 Building upon the idea of using laser points to show transmittance/absorption. 

1: Have a setup with some transparent colored objects (colored plastic, or dyed water, ect) and an array of colored lasers. 
2: Demo how some pass through and others dont/ explain absorption ect. 
3: Hid the colored objects behind a box, and let participants 'investigate' whats colors they think we have lined up. First, starting with just one color. And then layering some. Ending with how white light passes through them all.  
4: Tie back to engineering. Demo it on our finger/with a pulse ox, and drive home are we can use red and blue to measure oxygenation. 

We did something similar with gummy bears/lasers with middle school girls, and they really enjoyed it! They actually began layering them and seeing what happened when they combined colors on their own! And having a lot of colors is a fun exhibit for kids. 
-Quinlan]]> 2023-01-08 18:44:09 UTC https://padlet.com/fbonettamisteli/1xakudj1zz9fn2xm/wish/2436940950