how does it work

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Page 1: how does it work

Made by R.Sridhar

Page 2: how does it work

Washing machines clean clothing by forcing a water and detergent mixture through fabrics. The action of forcing detergent infused water through your clothing fabric is what enables the detergent to chemically loosen dirt embedded in the cloth and separate it from the fabric. Count your blessings; in the old days, people would beat wet clothes against a rock loosen dirt!

In top loading washing machines the ratchets back and forth dragging clothing down to the bottom of the washer tub. The clothes then move back to the top where the agitator grabs them again. In a front-loading washing machine, the clothes tumble through water in the base of the washer tub over and over again. After the water is pumped out, the inner drum uses centrifugal force to squeeze water from fabrics and clothes by spinning between 500 to 1200 RPM (revolutions per minute.) depending on the washer model.

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The process of converting gasoline into motion is called “internal combustion.” Internal combustion engines use small, controlled explosions to generate the power needed to move your car all the places it needs to go.

If you create an explosion in a tiny, enclosed space, such as a piston in an engine, a huge amount of energy is released as expanding gas. A typical car engine creates such explosions hundreds of times per minute. The engine harnesses the energy and uses it to propel your car.

The explosions force pistons in the engine to move. When the energy from the first explosion has almost run out, another explosion occurs. This forces the pistons to move again. The cycle continues again and again, giving the car the power needed to run.

Car engines use a four-stroke combustion cycle. The four strokes are intake, compression, combustion and exhaust. The strokes are repeated over and over, generating power. Let’s take a closer look at what happens during each phase of the combustion cycle.

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Intake:  During the intake cycle, the intake valve opens, and the piston moves down. This begins the cycle by bringing air and gas into the engine.

Compression:  As the compression cycle begins, the piston moves up and pushes the air and gas into a smaller space. A smaller space means a more powerful explosion.

Combustion:  Next, the spark plug creates a spark that ignites and explodes the gas. The power of the explosion forces the piston back down.

Exhaust:  During the last part of the cycle, the exhaust valve opens to release waste gas created by the explosion. This gas is moved to the catalytic converter, where it is cleaned, and then through the muffler before it exits the vehicle through the tailpipe

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In the refrigeration cycle, there are five basic components: fluid refrigerant; a compressor, which controls the flow of refrigerant; the condenser coils (on the outside of the fridge); the evaporator coils (on the inside of the fridge); and something called an expansion device.

1. The compressor constricts the refrigerant vapor, raising its pressure, and pushes it into the coils on the outside of the refrigerator.

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2. When the hot gas in the coils meets the cooler air temperature of the kitchen, it becomes a liquid.

3. Now in liquid form at high pressure, the refrigerant cools down as it flows into the coils inside the freezer and the fridge.

4. The refrigerant absorbs the heat inside the fridge, cooling down the air.

5. Last, the refrigerant evaporates to a gas, then flows back to the compressor, where the cycle starts all over.

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Electric fans are comprised of a motor run by electric current, which is attached to fan blades via a shaft. This rotor shaft is run by the motor, and turns the fan blades at different speeds depending on the speed set for the motor.

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The number of blades and the general revolutions per minute of the motor can vary greatly depending on the model of the electric fan.

While all fans, hand operated and electric, move the air that is in a room or space, only electric fans are actually efficient at cooling people down. This is because the energy expended to wave a manual fan creates heat in the body, and the fan's air does not do enough to counteract it. Additionally, the velocity of an electric fan changes the air pressure and lowers the temperature.

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Speakers come in all shapes and sizes, enabling you to listen to music on your iPod, enjoy a film at the cinema or hear a friend’s voice over the phone.

In order to translate an electrical signal into an audible sound, speakers contain an electromagnet: a metal coil which creates a magnetic field when an electric current flows through it. This coil behaves much like a normal (permanent) magnet, with one particularly handy property: reversing the direction of the current in the coil flips the poles of the magnet.

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Inside a speaker, an electromagnet is placed in front of a permanent magnet. The permanent magnet is fixed firmly into position whereas the electromagnet is mobile. As pulses of electricity pass through the coil of the electromagnet, the direction of its magnetic field is rapidly changed. This means that it is in turn attracted to and repelled from the permanent magnet, vibrating back and forth.

The electromagnet is attached to a cone made of a flexible material such as paper or plastic which amplifies these vibrations, pumping sound waves into the surrounding air and towards your ears

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