LASER is an acronym for Light Amplification by Stimulated Emission of Radiation. The LASER action was first proposed by Einstein.Applications of a LASERA LASER can be used in many fields. Some of its usages are given here.Used In Welding and Melting: The laser beam welding is mainly used for joining components using high welding speeds and low thermal distortion.Used In Holography: The reason that a hologram cannot be made without a LASER source is that coherence length for laser source can be very high due to which sustained interference pattern will be recorded on a hologram. This suggests the indispensable ... Read More

Yagi-Uda antenna is the most commonly used type of antenna for TV reception over the last few decades. It is the most popular and easy-to-use type of antenna with better performance, which is famous for its high gain and directivity. The frequency range in which the Yagi-Uda antennas operate is around 30 MHz to 3 GHz which belong to the VHF and UHF bands.Construction of Yagi-Uda AntennaA Yagi-Uda antenna was seen on top of almost every house during the 90's when we had only Doordarshan Channels. The parasitic elements and the dipole together form this Yagi-Uda antenna. It is seen ... Read More

To improve the radiation efficiency and directivity of the beam, the waveguide should be provided with an extended aperture so as to make the abrupt discontinuity of the wave into a gradual transformation, so that all the energy in the forward direction gets radiated. This can be termed as Flaring. Flaring is done to provide greater directivity and narrower beam width. The types of horn antennas depend on how they are flared.Sectoral HornThis type of horn antenna, flares out in only in one direction. Flaring in the direction of Electric vector produces the sectorial E-plane horn. As well, flaring in ... Read More

Microstrip antennas are the low-profile antennas. A metal patch mounted on a ground level with a dielectric material in-between constitutes a Microstrip or Patch Antenna. These are very low size antennas having low radiation. The patch antennas are popular for low profile applications at frequencies above 100MHz.Construction and workingThe microstrip consists of a very thin metallic strip placed on a ground plane with a dielectric material in-between. The radiating element and feed lines are placed by the process of photo-etching on the dielectric material. Usually, the patch or microstrip is chosen to be square, circular or rectangular in shape for ... Read More

Babinet’s Principle is actually the principle used in optics. According to its definition, “When the field behind a screen with an opening is added to the field of a complementary structure, the sum is equal to the field when there is no screen”The images clearly explain the principle. In all the regions, which are non-collinear with the beam, the above two screens, in figure 1 & 2, produce the same diffraction pattern.Case1Consider a light source and a conducting plane (field) with an aperture before a screen. The light does not pass through the opaque area but passes through the aperture.Case2Consider ... Read More

Sony Corporation is one of Japan's biggest multinational corporations, headquartered in Minato, Tokyo of Japan. It was founded by Akio Morita and Masaru Ibuka on 7th May 1946. It was during the wake of the World War-II. Sony’s first branded product was TR-55 Transistor radio that was launched in 1955, whereas Sony was made to be its official name since January 1958.It was Not-So-EasyEarlier, vacuum tubes were used, whereas, after the invention of transistors, the circuits became shorter and eventually the size of the equipment used got reduced. When TR-55 Transistor radio was launched which was made using a transistor, ... Read More

Although India does not yet have a good setup for Biotechnology, there are career options galore after you have completed your post graduate in biotech. Whether you have completed your post-graduation in Biotech from the reputed institutes in India such as, Tata Institute of Fundamental Research or Indian Institute of Science, or from any university situated abroad, it’s a high-level training that matters.According to industry experts like Dr. Yusuf Deeni, post completion of Masters in Biotechnology, one can find employment in biotech companies or can even pursue Ph.D.One can also be a part of biofuels, healthcare, cleantech and industrial biotechnology.For ... Read More

A smartphone is the most common device often seen in the hands of people, starting from the small kids to a 60 years old man. What is so special about this gadget? Does it only make life easier? What are the additional benefits this gadget offers? Numerous questions come to the mind of the users when they are buying the smart phone for the first time.For some folks, these gadgets are nothing but an instrument of entertainment. For some, it is the way to communicate to people around the world; some use it as the camera, whereas some may use ... Read More

A good teacher teaches the children putting his best efforts, whereas a better teacher evaluates the effects of his teaching on his students and tries to improve his way of teaching. End of the day, improvement in the status of the student and his learning is more important.An improved process called as Visible Learning was made by John Hattie to help the teachers evaluate their teaching process. It says, “Know Thy Impact” by showing what the teachers have taught and what did the students learn, which enables to understand the gap so as to bridge it.Visible Learning is the concept ... Read More

Earth rotates around its own axis which is tilted at 23.5 degrees, from the plane of its orbit around the sun, in the eastward direction. It takes almost 24 hours to complete one rotation. The Earth rotates at a speed of 460 m/s, that is approximately 1650 km/hr at the equator. The angular velocity of the Earth decreases as we keep moving toward the poles.The Earth's rotational speed is slowing down with time. According to atomic clocks, the present day is 1.7 milliseconds slower than a century ago. It is not a big issue as it will take more than ... Read More