CD ( Compact Disc ) must spin very fast to read it.
The hole is for the motor to catch it at the center and spin it round and round.
If no hole, CD would wobble and fall..
Hole helps factory machine to hols the CD when they make it.
All discs like CD, DVD have hole at the center for the same reason
TO SPIN PROPERLY !!!
This information was shared on Koun Banega Karodpati program.
Actually judo was not fully banned forever !!!
It was banned for a short time in Japan after world war Ii by allied occupation.
After world war II ended, America and its allies were in charge of Japan.
They said, " No judo, No karate for 5 years !!! "
Why did America and its allies banned Judo ??
They thought Judo was used to train soldiers.
They didn't want Japan to learn how to fight again !!!
After 5 years, ban got ended.
Then Judo became a sport. Not for war ......
Judo was banned ......
Not by Japan but America and its allies !!!
Banned only for 5 years......
Now Judo is Japan's No. 1 sport.
India has won gold medal in Judo in Commonwealth games 2026 !!!
Yesterday, I had written a blog article on Why our fingers get wrinkled ??
This is the continuation part......
Our nerves and blood vessels react differently to temperatures . !!!
Hot water opens up blood vessels and makes nerves more active.
So our body gets shrinking signal faster as nerves are more active.
Also, outer skin swells faster in hot water.
Wrinkles show up in 3=5 minutes in warm water.
Cold water makes blood vessels squeeze and nerves to slow down.
As nerves have slowed down, even shrinking signal takes longer time to reach nerves !!!
We get wrinkles in around 10 minutes !!!
So, we do get wrinkles both in hot and cold water. But we get wrinkles faster in hot water !!!
Its our nervous system doing it on purpose !!!
The top layer of our skin has only dead skin cells and keratin. It soaks up water and swells.
The layer underneath has blood vessels and nerves.
When we are in water for 5-10 minutes, nerves under the skin makes the blood vessels to get smaller.
So, outside gets puffy whereas inside skin is getting smaller !!!
Result :
Skin wrinkles up to get fit
It wrinkles in lines because that is where the skin is attached tighter.
If nerves to our fingers are cut , our fingers don't wrinkle in water anymore !!!!
So, skin wrinkling is the work of nervous system......
Wrinkled fingers work like tire treads. They channel water away so that we can hold wet things in better way !!!
So, skin wrinkling is for better grip.......
Rats are not anyone 's favourite animals !!!
But these small rodents have lived with humans over centuries.
Here are some fascinating facts ----
1. Group of rats is known as " mischief " !!!
2. Rats are mostly active at night.
3. Rats have travelled the world with humans !!!
4. Teeth of rats never stop growing.
5. Whiskers of rats are more sensitive than fingers.
6. Rats can see in different directions at the same time.
7. Rats can hear the sounds that humans can't.
8. Rats leave behind a lot of droppings.
