Here are 4 physics puzzles involving rotation. See if you can figure them out without looking at the answers.
A Great Time to Observe Mars
Hello all, I just wanted to put up a short post to let you know that now is a great time to observe the planet Mars. This is because Mars and Earth are in their closest approach these next couple of days with May 22nd being the best day (see figure below from NAOJ).
This would be a great time to pull out a small telescope or binoculars to get a glimpse of the Red Planet. A great summary of how to observe mars is here at Cosmic Pursuits. Below is an image of where Mars will be in the sky for the next few nights from NASA.
One last thing, you may get an e-mail message claiming that Mars is going to be as big as the Moon in the sky, DON’T BELIEVE IT! If Mars was close enough to Earth to be as big as the Moon we would all be in trouble! No one is quite sure where this hoax started but it seems that someone got mixed up between Mars being as BRIGHT as the Moon, and being as BIG as the Moon back at the closest approach in 2003. And every August since then the hoax seems to make a comeback.
Go enjoy Mars and keep looking up!
Transit of Mercury
Today’s post is not really a science prompt but more of an announcement. This Monday, May 9th, 2016, Mercury will pass between the Earth and the Sun. This happens about 13-14 times a century so it is a relatively rare event. I am hoping to pull out a couple telescopes to view this but it looks like it is going to rain here on that day. If you want to view it you will need a system with at least 30x magnification since the planet Mercury is so small but make sure you VIEW THE SUN SAFELY. Go here to see how to view the transit safely. If you cannot view the transit from your location it will be broadcast online by both the NASA Solar Dynamic Observatory and by Slooh Observatories. Watch the video from Science@NASA below for more information. Enjoy!
A Handyman’s Lesson in Center of Mass
I came across this great idea from Scientific American. Check it out and see if you can come up with similar projects to try out.
Brick vs. Tennis Ball: An example of what a science prompt can become
This video was posted recently by the YouTube channel Stand Up Maths where a simple apparatus of a brick and tennis ball tied together leads to the derivation of centripetal force. The math in this video is a little high but this is the sort of thing I would love to see in a science prompt.
- Start with a simple set-up.
- Ask a straight-forward question.
- Seek the answer.
Here is the video:
At Home Particle Detector
Using materials you probably have lying around the house and some dry ice you can detect high-energy particles coming from elsewhere in the cosmos.
What you need
- large clear container (a fish tank works well, or for a smaller scale detector use a jar)
- a sponge
- 91% rubbing alcohol
The two videos below give the instructions for building this project. Enjoy!
The image at the top of this post is by Own work – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4973453.
The Amateur Scientist
Ok, so this isn’t a normal science prompt but I wanted to post this for those who might be interested. If you are looking to go deeper in your science endeavours, check out the old column from Scientific American called “The Amateur Scientist.” This column gives instructions for building high-energy particle detectors, rocket fuel, homemade grappling hooks, and dredge nets. There is a little bit of everything here but these are more advanced (and sometimes more dangerous) projects. Check it out, even if you don’t actually do the projects I think it is worth the read. It will give you a better appreciation for how science is done.
Unfortunately, the Society of Amateur Scientists seems to have shut down but there is still a Facebook page you can check out.
Homemade Cloaking Device
A simple setup to make things disappear.
What you need: vegetable oil, at least 2 items made from pyrex glass (be sure that one piece of pyrex will fit comfortably inside the other).
Fill the larger container with vegetable oil. Slowly and carefully drop the second pyrex glass item into the vegetable oil. If you are using a small dish or test tube make sure you allow it to fill with the oil. The second piece of pyrex will disappear right before your eyes.
A couple example videos are below, enjoy!
Great Homeschool Convention Resource Sheet
Thank you to all those who came out to the Workshop I gave at the Great Homeschool Convention in Cincinnati tonight. Below is a link to the PDF of the resource handout I gave at the talk in case you didn’t get one or lost yours. Also, you can find more resources on my amazon resource page here. Shortly I will post a summary of the demonstrations that I did during the workshop. Enjoy!
Download the PDF here.
Leave a comment to stay up to date with improvements to this website.
Also, here is the Veritasium video I referenced in my talk.
Science Prompt: Waves on Strings
Collect a bunch of different types of string and rope. Yarn, sewing thread, jump ropes, garden hose, any of these will do. The more variety you can find the better. For best results the strings should be at least 4 feet long, 6-8 feet long would probably work best.
Have a person hold the string on each end. Have one person shake their hand up and down once quickly. Watch the wave travel down the string. What affects the speed of the wave? This is where the different strings come in, try to reproduce the same tension with a different string. Do you see a change in speed? Change the tension on the string. Do you see a difference now? What else can you change that might change the speed.
DIY Homeschool Science Curriculum 