You can make a beautiful Rainbow display to decorate your show case to give a “Visual Treat “to the visitors. It emits all the colours of the Rainbow (VIBGYOR) one by one and finally flashes rapidly. This is a kind of simple “Mood Lamp” to elevate the mind of viewers. You can fix it in an empty Jam pot so that it appears like a “Rainbow pillar”. A Multi colour Flashing LED and Glue stick can do this Magic. Multicolour LED has three chips to generate Red, Blue and Green (RBG LED) lights. Due to the fast transition of colours from one to another, the colour mixes and gives the Rainbow display. The Gluestick commonly used with the Glue gun transmits this light to its entire length giving a good visual effect. So try it, you need only Rs.25 for this. Continue reading →
Use this simple circuit to detect the presence of Alcohol. This kind circuit is used by Police officials to prevent drunk driving. It gives a beep when it detects the Alcohol vapour. MQ3 Alcohol sensor is now readily available and you can make the device very easily. When the Sensor detects alcohol vapour, it gives output voltage depending on the concentration of alcohol molecules in the air. Continue reading →
Not always, but only when handled carelessly. Shock induced muscle tetany is the most important effect of current on the muscles. If a person touches the energized conductor, fore arm muscles contracts forcefully and fingers bend. So the person involuntarily holds the conductor. Therefore the victim will be unable to take the hand from the conductor.
As you know, electricity is the flow of electrons through a conductor from its source to the destination. If the conductor offers less resistance, the flow current will be fast and if the conductor has some resistance, the flow of electrons will be obstructed leading to slow movements which generate heat through friction.
Human skin is a semiconductor for electricity and current passes through the body to the ground just like the flow of current through the electric wire. This flow of current causes burning and shock. If the skin resistance is low, the chance of shock hazard is very high. Some people are more sensitive to current while others are less sensitive. Electrical safety measures are necessary while dealing with high voltage AC available from the power grid. Ignorance can lead to a fatal shock or fire hazards.
Remember, Electricity travels at the speed of light. Its flow is around 299,460 kilo meters per second so you will not get time to react because you can’t move faster than electricity. So the best way is staying out of its way. Continue reading →
Our brain can learn , think and grow through interaction with the environment by perception and action.The human brain has the ability to adapt and rewire itself.During daytime, the brain receives millions of visual, auditory and other information which are processed during sleep to retain them as memory.Heavy workload of the brain makes it tired .Neurobics is the brain exercise using the five senses to rejuvenate the brain cells. Mental stimulation improves brain function and protects against cognitive decline. Continue reading →
Pheromones are biologically active substances secreted from the body of animals that elicits physiological and behavioral changes in another individual of the same species. Pheromones are ectohormones released from the body to exert influence on another animal of the same species. The word Pheromone is derived from two Greek words Pheran which means to transfer and Horman to excite. Humans, like other animals also release pheromones from the body, but its quantity is less significant since it has no relevance in communication. Human pheromones do not have to be consciously perceived to affect the recipient, but have been shown to affect our behavior when used at subconscious levels. Continue reading →
Closed Circuit Television (CCTV) is now common in commercial establishments, banks , home etc to monitor the premises for discouraging theft by recording the criminal activity. The system uses a video camera to transmit the signals to a specific place on a set of monitors. The signal is not transmitted open but transmitted to limited points through short range transmission. The receiver is connected to a TV. In wired system, RF cables are used to connect the camera directly to the TV. The Digital Video Recorders (DVRs) provide recording facility continuously with extra features like motion detection. The IP based CCTV has mega pixel sensors help to record the data directly to network attached storage devices for completely stand alone operation. High Definition CCTV (HD CCTV) system is now available to identify and track the objects in their field of view.
Bluetooth is the miniature wireless transmitter and receiver used as an interface to access LANs, PSTN, Mobile network and portable handheld devices. Bluetooth can communicate with the Bluetooth enabled devices through a short range network called ”Piconets”. When the Bluetooth enabled device enters the proximity of the piconet, it establishes connection with the Bluetooth.It is very useful for hands free communication in hand held devices. The technology of Bluetooth was named after Harald Blaatand Bluetooth II, the king of Denmark.