Flying like a Jelly Fish

Don't go crazy when you see the title, What I am about to say is a innovation by Lief Ristroph and Stephen Childress of New York University. You might have compare an aero plane to a bird and an helicopter to dragon fly in some day of your life. Both of these are animals who can fly, but did you ever thought that the researchers would be able to engineer a miniature flying machine using the swimming motion of a jellyfish?

As I have also said earlier most flying machines we have seen in our days mimic animals birds or insects, they tend to flip upside down unless they have special mechanisms called aerodynamic dampeners which are basically tails or sails; or a continues control system to control the wing speed and the motion. But this flying machines mechanism which mimics the jellyfish swim allowed it to maintain stability without adding those mechanisms.

This jellyfish flying machine is called a "Thopter" which weighs about 2.1 grams including the motor which weighs 1.1 grams still in experimental stage. Researchers would be one day able to get this flyer to a commercial stage.

For the ones who need to see how the jellyfish swim:

Resources:
LiveScienceVideos : YouTube channel
Facts from Royal Society Publishing

Measurements

We all know that we can measure things with certain units that we all have agreed upon. There are two

Vernier caliper

systems at work at the current time; Metric System and the Imperial System. Both of these measure with

1. Length
2. Area
3. Volume
4. Mass and Weight

The standard in scientific measurement is mostly the metric system. But still there are countries that use imperial system instead. While the Metric system measures using a decimal system imperial system uses otherwise. It doesn't have a pattern to my point of view. But the Metric system also known as the SI (International System of units) has a well organised pattern and a prefix for most of the points. Since the majority of usage, we will discuss only about the Metric system.

There are 3 sub systems in Metric System.

1. Centimeter-Gram-Second System (CGS)
2. Meter-Kilogram-Second System (MKS)
3. Meter-Tonne-Second System (MTS)

We can use either of these systems as per the scope of our measurement. Normally we use MKS system for our usages. Hence we measure

• Length by Meters: suffix 'm'
• Area by square meters: suffix 'm^2'
• Volume by meter cube: suffix 'm^3'
• Mass and weight by Kilograms: suffix 'kg'

There are a lot yet to be explained. To keep the post simple, I'd stop here. Will meet you with another Post!

Resources:

Images

#1: wfmprophecies.blogspot.com

#2 www.craftsmanspace.com

Information from: http://en.wikipedia.org/wiki/Metric_system and http://en.wikipedia.org/wiki/Imperial_units

The Speed of Light

The speed of light is the amount of distance the light travels for a unit of time. More over it is 299,792,458 m/s to be exact. Some times we take this value to be 3x10^8 as it is easy for mathematical calculations and this is commonly denoted as c. As in the popular equation E = mc^2 (c here is the speed of light and, m is a mass). This is the maximum speed in which any matter, energy or any other thing can travel.


For short distances this is a speed that the human eye would not be able to pick up. Which means it is almost instantaneous. But for long distances such as sun to earth, this would be very noticeable. Did you know that the time to travel the distance between the earth and the sun is about 8 mins and 17 seconds? This means we would not notice if something happens to sun immediately but we would know that after 8 mins! Amazing right?


This speed can be different to which the light is travelling. For transparent materials such as air, glass or water, the speed of light is less than c. The ratio between the speed of light and the speed of light through another material is called the reflective index of the material. This is the reason to refraction or reflection of light off materials.




Light Years is a unit to measure distance. It is the amount of distance the light travels in an year. This ads up to about 9.4605284 x 10^15m, That is a long distance!

Picture courtesy: http://scienceblogs.com/

Resourses:

Wiki: http://en.wikipedia.org/wiki/Speed_of_light

And my own physics teacher at school! :)