Thursday, 17 November 2016

Working of Mini Tesla coil.

https://www.youtube.com/watch?v=cSM2kaaWwsk

Components used :

1. Transistor =  PN2222A
2. Copper wire =  26gauge
3. 9V battery
4. Resistance =  22K





Here, the transistor is working as a switch which is continuously being reverse biased (off)  by the back EMF induced in coil 1 (primary with 3 turns). This is happening at high frequency.
 
when we close the switch current starts flowing through emitter to base(5%) collector(95%) .
The collector is connected to primary coil  and when current passes through it , it creates an induced EMF in secondary coil which in turn creates a back EMF in coil 1 and hence coil 1 makes the Collector -Base   reverse biased(off).

 This is (ON/OFF) is happening at high frequency.

Also, some amount of current is being fed to the secondary coil through Base but the upper end of this coil is left open  due to this ,the secondary coil creates a heavy voltage to throw it in air.

High voltage means strong electric field that is why whenever  a CFL comes in its electric field it starts glowing.

SOME INFORMATION
1 . The voltage created is as high as 870V ( nearly).
2. For larger tesla coil you can use transistor BD135



THANKYOU  :)



Friday, 28 October 2016

VOLTAGE BEHIND ELECTROCUTION..!

https://www.youtube.com/watch?v=smlC45_CqGk

Before starting any experiment its a must thing to ensure the safety  measures.

So if you spend your time with power source and electrical appliances, this post can be boon for  you.

According to Ohm's law    V=IR
                                                I=V/R

WHEN we touch the live wires of any (ac/dc ) source then it doesn't matter how much current is coming if the potential difference is not enough (to break the resistance of our skin)  we r safe.
 
According to scientific experiments if current  of

  • 1 -10 mAmps flows = we feel it get small shock.(licking 9V battery)
  • 10 m Amps = we may stuck to the conductor.
  • 20- 30 mAmps = muscle contraction ,it become touch to breath.
  • 70-100 mAmps = heart beating abnormally.
  • 500 mAmps = heart may stop DEATH.
  •  



Resistance of our body(fingure's skin) varies between 100k to 1300k .(better you measure it with multimeter.)

To break this high resistance it require nearly >50V (a safe limit it can be high  ~80v)

So, if  you play with (upto 50V (AC /DC) )you r safe going higher means you r in prone zone.

When you lick the two electrodes of 9V battery some current(~3-4mAmps) flows due to low resistance of our tongue .such little current cause a sharp shock then you can imagine what higher current (in Amps) can do.


In reality DC is more dangerous than AC as it can easily burn human body because it if uni-directional nature.but it needs two electrode which reduces its ill effects.

AC can create it own loop (because of its reversing direction)and may not need other wire (it can run through ground ) can easily electrocute you.

To know more....
WATCH MY EXPERIMENT ON YOUTUBE.
https://www.youtube.com/watch?v=smlC45_CqGk