Happy Pi day..

Probably not the most celebrated holiday but I think its cool to be able to celebrate it on march 14 which is 3.14 which is how Pi starts off..  I think this celebration is started by Exploratorium (my most favorite science museum in the world) 24years ago.  And I think it also coincides with Einstein's birthday too!!! who ofcourse is even on our logo:)

Here's a fun experiment I came across last year and an easy way to teach children the relationship between the diameter and circumference and Pi (ofcourse).

Take any circular object and carefully wrap a string around the circumference of the object.  Cut the string to exactly the length around the object. Now the string is exactly equal to the circumference of the object.  Take this string and stretch it across the diameter of the circular object. Cut the string to the length equal to one diameter.  Repeat the procedure again. How many diameters could you cut? 

Now try with another circular object.  What do you observe?
 
No matter what size circle you use, you’ll be able to cut 3 complete diameters and have a small bit of string left over. And the string left over is the length on the other side of the Pi.  (3.14159 26535 89793 23846 26433 83279 50288.....).

Have a fun Pi day
Sheela

Another successful science fair....in the words of parents

Last friday, I held another Science Fair in our son's Kindergarten class.  Took about 10 exhibits of various sizes including bubble one, chinese spouting bowl (my personal favorite), a couple of magnetic exhibits, earthquake table exhibit....  The children were excited and liked almost all the exhibit, different kids liking different exhibits.

I asked the parents to give me some feedback which ones they liked, what they liked and didnt like about Science Fair.  Slowly I am beginning to gather feedback and so far, it has been very positive.  Wish I could have taken some pictures to capture those emotions but am really happy to hear kids remembered and gave such a positive feedback to parents.

Answer to the last question is - Hot water freezes faster than room temperature water with everything else being the same (same type of container, same freezing conditions etc.  Its called Mpemba effect named after a high school student in Tanzania.... Ofcourse you might not see the same effect if say you put hot water in one and really cold water in another as the temperature difference between really cold water and freezing point might be too little for Mpemba effect to occur.

Another experiment/question coming soon....
Have a great Science week

Hot water or cold water

Question I have been asking quite a few people in the last few days - If you have two bowls, one with hot water and another with room temperature (or colder) water, which one will freeze faster....Not a trick question...

Try it at home and let me know.... ask your friends and have fun with it...

Have a happy science sunday everyone

Silicon Valley Science and Technology championship...

Today, I went as a volunteer to judge in Special Awards Category to the Silicon Valley Science and Technology championship in San Jose.  Its the biggest Science Fair I have attended so far.  It was just so awesome.  The caliber of projects that students put together was just mind blowing.  The fair was for 6-12th grades and I was looking mostly at 6th and 7th grade projects.

Saw quite a few projects even at 6th grade level on solar and Wind Power.  And quite a few on day today issues we face all around us...

Now for the answer to the previous question - How to blow warm air or cold air from our mouths...

If you blow with an open mouth slowly on your hand, it feels warm but if you blow with your lips closer (a narrow band of air), it feels cold.

The reason for the same air to feel warm or cold has to do with mixing with the air once it comes out of the mouth.  When you blow with an open mouth, a wider jet of air comes out and it doesnt mix with the outside air nearly as quickly and it still feels warm (temperature of the air coming out of our lungs).  But when you blow with pursed lips, the jet of air is narrow and the air tends to mix with the air around it and feels cooler.  If you blow air with pursed lips but your hand is very close to mouth, the air does feel warm as it doesnt get mixed with outside air quick enough...

till the next science question...

Good night

blowing air with mouth

Can you blow warm air with your mouth?  How?  Can you blow cold air with your mouth?  how?

post your answers in the comment section ...

want a bigger monitor to work on? how about your dining table?

I love the era we are living in.  Never know what I new cool things get invented and 24hrs is not enough to read all about them.  I was reading about this cool technology and wished its available today:)

Whether we are using our computer or playing video games, we always wish for bigger screens right...well, at least I do:)  and Light Blue Optics are coming up with a product that will convert any flat surface into not only a screen, it converts into a Touch Screen!!!  Awesome...I just have to clear up my floor of all the toys and books and squat down for the biggest screen to read up on the next cool thing thats coming out:)

The product called "Light Touch" uses Holographic Laser Projection technology (yet another use for Lasers) to create images and infra red sensor to convert those images into interactive mode thus creative any size touch screen you want.  AWESOME!!

Seems like we can soon go to a restaurant and instead of paper menus, we just see the menus on the table and pick what we want to eat that gets directly sent to the kitchen!!  

check out their website for video/pictures.  http://lightblueoptics.com/

Have a great Science weekend...