08 November 2009

Quarks?

I was asked is there anything smaller then a quark. Well that can be a tough question and to think it was posed by an 8 year old. This will be a very basic overview of the characteristics of a Quark. Quarks and the associated Leptons are complicated. This will be a basic overview and more questions are bound come from this so please ask me and we will learn together.

Lets start with what are Quarks and Leptons: Quarks and Leptons are the building blocks of matter.

Because they are so small they are normally referred to in cross section as that is a better way to understand them then by mass. But to give you an idea molecules are made of Protons, Neutrons and Electrons. One Proton is made of 3 Quarks. Quarks can be found in 6 different varieties and all have different characteristics or "colors"

But if you look at Leptons there are smaller particles called Neutrinos. These are referred to in experiments as: "the results are consistent with zero mass for the neutrino".

This is all part of Quantum Physics. As I stated before this is a complicated question with varied answers. The physicists have more questions then answers about these small particles that cannot be seen only their effects on each other is observed.

Please continue to explore this field and ask more questions. Below are a few links that I used to help my understanding.




18 October 2009

Kids' Science Challenge

I wanted to let everyone know who has a child in 3rd to 6th grade that there is a science contest for them. This is the "Kids' Science Challenge" sponsored by Pulse of the Planet. (I have not checked out the Pulse of the Planet website so I do not have any recommendations about it at this time).

I have checked out the challenge and feel it is a great opportunity to let your kids be creative and explore the ideas they have. There are 3 catagories:
* Sports on Mars
* Detective Science
* Bio-Inspired Design

There are scientist to help them online and lots of fun information even if they do not want to submit an entry.

Please let me know of any entries that are submitted. I also would be willing to answer questions your kids may have. Remember that parents must actually sign your kids up in order to submit their entries.

I have placed the link on the side of this site and in this posting.

Good luck to all of you!!

23 September 2009

Speed of Sound

Does the speed of sound change with elevation?

Yes it does is the short answer but because I learned from my father that is never the way to answer here are the details.

The basic formula for finding the speed of sound is:
c = \sqrt {\kappa \cdot R\cdot T}

  • R (287.05 J/(kg·K) for air) is the gas constant for air
  • κ (kappa) is the adiabatic index (1.402 for air)
  • T is the absolute temperature in kelvins
As can be seen by this the only thing that changes is temperature. As the temperature is lower the speed of sound is slower. This is the primary reason that sound is slower at higher elevations, the air is cooler there.

Just some examples the speed of sound at sea level is about 760 miles per hour and it is about 660 miles for an airplane.

Now what about sound through a solid object?

The stiffness and density of the material will affect the speed. Stiffness will will increase the speed and density will slow it down. This can make the calculations complicated. Here is the basic formula used to calculate the speed through solid materials:
c = \sqrt{\frac{C}{\rho}}
C is a coefficient of stiffness
ρ is the density
There are other variations of this formula to calculate for liquids and gases.

Most of the information for this post was obtained from:

http://en.wikibooks.org/wiki/Acoustics/Sound_Speed

http://www.engineeringtoolbox.com/speed-sound-d_82.html

There is also a great slide show that has some examples and video of sound and speed: http://www.slideshare.net/darrella/speed-of-sound

Please post comments if you want clarification about any information in this posting or have any comments or questions.

Keep exploring your world.

23 August 2009

Cool Jelly Fish video

As any good scientist I must give credit for where infomation is obtained. One of my favorite radio shows is Science Friday I get a lot of information from them and it is easy to listen to while I am working. One of their features is a video of the week. This is one of the really cool ones. In this video you can see how jelly fish swim. This is being used to study how much mixing of the oceans is occurring.

Watch this and let me know what you think video

22 August 2009

Mars

Mars will be closer to Earth then it has been in recorded history. This will culminate on the night of 27 August at about 1230 am. I would encourage you to allow your children to stay up and see it. This will not occur until 2287 (at the earliest) If you have access to a telescope or binoculars then bring them out with you. Mars will be observed next to the moon and will be the brightest object in the night sky.