MAKING AN AUTOMATIC LETTER ALARM

The Simple Circuit described in this project is based on the fact that a bulb glows when there is a letter in the letter box. It is an on/off device operated by the weight of letters. When the switch is pressed , if there is letter in the box, the bulb glows,otherwise not.

You Require

• One letter box (16" X 10" 5")
• One electric bell
• One bulb of 15W220V with bulb holder
• Plastic Coated wires
• Tin plates about 1.5 cm wide
• 4 screws of one inch size
• Sellotape or black tape 

What to Do

• Get a letterbox made of wood by a carpenter having a size of 16" X 10" X 5". The top of the box from where the letter are to be dropped should be at an angle of 45 degrees . The opening of the box should be in front.
• Before Fixing the front side of the box , all the electrical connections should be made.
• About 7" from the top inside the box, a tin plate made in half-U shape be fixed with a screw in such a way that the curved side must face you. About 1 cm below, there should be another straight tin plate fixed with a screw . These two tin plates should not block the way of the letter . They should be fixed in such a way that the letter slides down easily. A bell should be connected with the plates. The bell will ring with a little touch of letters to the plates. As soon as the letter slides downwards , the bell stops ringing.
• At the bottom, about 1" above the of the box, two tin plates 8" each should be screwed horizontally with only a little gap of about 3mm to 4mm. These plates should also not touch each other as they are the key of the circuit.
• To the horizontal tin plates, to other small tin plates one to one horizontal ones should be fixed, so that the letter falls sideways, it can exert weight on the plates for the circuit to be colmpleted.
• A switch should be connected in the bulb circuit so that it does not glows continuously.
• When the wiring is complete and a letter is dropped into the box, the bulb will glow and the bell will ring.

Scientific and Very Logical Proof that UFO's Exist.

                   U.F.O.'s are real

 

All of us might have seen movies , played games and or might have seen pictures of U.F.O's. How do they look ? The most general look of a U.F.O is that of a flying soccer which is rotating. The design might be so simple and can be thought of as the imagination of a ten years old child. But if we observe carefully we will find that if there are U.F.O's then the are of the shape of a soccer. The shape is most perfect for a long journey spacecraft which have to travel many light years. The aliens, from wherever they might have come from , would have gravity on their planet, Since it is the fundamental property of mass. Since they are coming from very remote parts of the universe, it would take them a long time to reach earth. So they would have to create something called artificial gravity to survive so long in the space and that is the place where this design helps them.

When we have to separate any type of suspension or colloidal solution , we leave it undisturbed for a long time and the particles settle down at the bottom due to gravity. Imagine, What you would do to separate any colloidal solution in space by using any physical force other than gravity. You might have heard about centrifugal force. When an object revolves around a fixed point the it observes a force towards the direction of tangent. To create artificial gravity we do the same. So the rotating of the flying soccer is a very scientific thought which the people who have reported to see flying objects do not even know of. Why is the design same everywhere? Perhaps we know the answer and it comes out of a very simple logic.

Please comment your views...thankYOU..

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Making a train floating in air at home.

                  Making a train model that runs in air

This project is based on a phenomenon known as ELECTROMAGNETIC LEVITATION . It simply means making an object stay in the mid air using an electromagnet. But How Does It Works??

Now, Imagine a magnetic object sticking to an electromagnet  and the electric circuits breaks, the object is falling down but before it could get out of the electric field, the circuit completes again and the object starts coming up again but then again the circuit breaks . What if this happens at a very fast speed??

The object will remain in the air. This is how electromagnetic levitation works.

But how to make a circuit that breaks and connects very fast ?  In sophisticated labs this is possible using advanced machines but what how can we do this at home. I Wanted to do this , So I thought ..... thought.... and yes thought. Then one day a great and very simple design got in my mind.

Lets take a look at it. This is how it works

 

The fan is made using any light conducting sheet (could be of aluminum ) When the fan is straight, it's end touch the wires and the circuit completes and when its position changes the circuit breaks . The fan will complete at least 20 rotations in a second it means the circuit will break and join about 40 times. It will be enough for us. I would suggest to make the object also out of aluminum sheets so that it may not become to heavy to get attracted by the magnet. Use enough power, large no of turns and soft iron rod for making the electromagnet.

Have fun.

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