Switched Mode Power Supply uses a switching regulator to convert electric power efficiently. SMPS transfers electric power from a source ( AC mains) to the load by converting the characteristics of current and voltage. SMPS always provide a well regulated power to the load irrespective of the input variations. SMPS incorporates a Pass transistor that switches very fast typically at 50Hz and 1 MHz between the on and off states to minimize the energy waste. SMPS regulates the output power by varying the on to off time using minimum voltage so that efficiency is very higher compared to the linear power supply.

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Toothed Whale uses Bisonar system

Echolocation evolved in aquatic mammals about 30 million years ago during the Eocene period. Whales and other aquatic mammals like Dolphins, Seal, Porpoise etc use Ultra sound for navigation and predation. Whales live in an environment that has acoustic characters but with low visibility due to the turbidity of water. So they use the sonar mechanism for navigation. Whales, especially Toothed whale uses Bisonar system for echolocation. Bisonar in toothed whale uses two frequencies like FM and CF for locating the objects. Sonar is a system that detects objects through sound waves. The word SONAR is the acronym for SOund Navigation And Ranging.

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Bat uses FM Frequency

Echolocation is the biological sonar system used by some animals to navigate or locating prey. They emit ultrasounds in various frequencies that reflect back from the objects. These animals have special ear and brain adaptations to detect the reflected sound. Echolocation is found in animals like Bats, Toothed Whales, Shrews, Dolphins and in some birds. The interesting feature is that Bats emit FM frequencies for precise range discrimination and localization of the target.

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PIR Sensor

Infrared is the invisible radiation lies between the Visible and Microwave portions of the electromagnetic spectrum. The term Infra means below the ability to detect visually and the term Red means colour of the light with low energy level. The Near infrared is close to the red portion of visible light and the Far infrared is close to the microwave region. Far infrared is thermal and we feel it as heat by the temperature sensors in our skin. Short and Near infrared rays cannot be detected since these are invisible as well as cool. Active infrared rays are produced from semiconductor sources but natural objects like animals including human beings emit infrared rays from the body heat. Humans at normal body temperature emits Infrared rays at the wavelength of 10 microns.PIR Sensors are used in surveillance systems to detect moving persons in protected areas.

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Compact Fluorescent Lamp

Compact Fluorescent Lamp or CFL is the energy saving lamp designed to provide adequate light at the expense of low current.CFL uses less power around one fifth of an ordinary bulb and has long life.CFL is designed to emit Soft white light using the phosphor formulations.CFL comes in two forms like integrated and non integrated CFLs. In integrated type, the tube combines with an electronic ballast as a single unit while in non integrated type, ballast and tube are separate units so that the tube can be replaced.AC and DC CFLs are available.CFL generally has a life span of 6000 to 20000 hours.

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Induction Heating

Induction heating is the heating of an electrically conducting material using the energy from Electromagnetic radiation. The process of electromagnetic induction creates Eddy currents (Foucault current) in the conductor and by the process, the resistance causes the conducting material to heat up due to Joule heating. Induction cooking is the Flameless cooking that exploits the ferromagnetic property of some metals and electromagnetic induction.

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MOSFET is the Metal Oxide Semiconductor Field Effect Transistor used for switching applications or to amplify signals. In the MOSFET, a voltage applied to its oxide- insulated gate to induces a conducting channel between the Source and Drain electrodes. This causes the flow of current. The channel may be n-type or p-type and based on this, MOSFETs may be n-MOSFET or p-MOSFET. Previously, metal was used in the gate but now polysilicon is used in the gate but the efficiency is more in metal made gate channel.

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