It is quite a common view if you stay in Eastern countries that you see mirages under the hot scorching sun while driving on roads, especially during afternoons. You can find yourself to see a small pool of water on the road while there won’t be anything when you approach there. Though it is a bit surprising, there is a simple theory behind it.Why Does It Occur?Mirages happen when the land is hot and the air is cool. When the land (the asphalt road or a desert land) gets heated up due to hot sun, the air just above it ... Read More

A bank is a place where you secure your money. But when the Doomsday arrives and everything collapses, what do you need for the survival? Yes! It’s food. The source of food for the world is, of course, a seed.Mankind can survive if food crops can be cultivated even after facing the Doomsday. Exactly with this thought in mind, a Doomsday bank was established and is maintained in Norway, storing the seeds of nearly one-third of all the precious varieties of food crops.Svalbard Global Seed VaultOn 19th June 2006, the first stone was laid for its construction and a very ... Read More

A Directional coupler is a device that samples a small amount of Microwave power for measurement purposes. The power measurements include incident power, reflected power, VSWR values etc. Directional coupler is used to couple the Microwave power which may be Uni-directional or bi-directional. It is a 4 port waveguide junction consisting of a Primary main waveguide and a Secondary auxiliary waveguide. The below figure shows the image of a directional coupler.PropertiesThe properties of an Ideal directional coupler are as follows.All the terminations are matched to the ports.When the power travels from port 1 to port 2, some portion of it ... Read More

Whenever a current carrying conductor is placed in a magnetic field, it experiences a force. The relation between these three is stated by Fleming’s left-hand rule. To understand this rule, the thumb, middle and index fingers are placed in perpendicular to each other.Thumb RuleImagine a current carrying conductor placed in-between a horseshoe magnet. This magnet produces some magnetic field which will be in the direction indicated by the forefinger or Index finger. The current passing through the conductor will be in the direction of the middle finger. This conductor experiences a force which is indicated in the direction of thumb. ... Read More

Recently there have been many stand-up comedians coming up with extraordinary talent. I watch many stand-up comedy shows on YouTube and the ones conducted by Canvas Laugh Club (CLC) are my favorite. The list of comedians I would jump to watch is Kenny Sebastian, Aditi Mittal, Amit Tandon, Baggy, Alex, Rehman and so on.TV StarsThere are many comedians who are being in limelight recently, starting from the list of television stars to YouTube stars. Among the television stars, the recent sensation Kapil Sharma who has gained a huge fan base in India as well as in abroad with his show ... Read More

Milkha Singh is an ill-fated Sikh who had to witness his siblings and parents being slaughtered in the violence created during India-Pakistan partition, one who had to spend some time in Tihar jail for travelling in train without a ticket and the one who thought of becoming a dacoit. But, his sibling Malkhan persuaded and guided him to prepare for Army recruitment exam in which Milkha got succeeded in his fourth attempt in 1951, which gave him a chance to join the army. Milkha got introduced to sports through Army when he got selected for special training in athletics. This ... Read More

A helical antenna is another type of wire antenna, which is widely used for a higher range of broadband VHF and UHF applications. The frequency range of operation of the helical antenna is around 30MHz to 3GHz.Helical antenna or helix antenna is the antenna in which the conducting wire is wound in a helical shape and connected to the ground plate with a feeder line. It is the simplest antenna which provides circularly polarized waves and used in extra-terrestrial communications in which satellite relays etc., are involved.It consists of a helix of thick copper wire or tubing wound in the ... 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

Tirupathi is the highest visited temple on this earth till date, having Lord Venkateswara or Balaji as the main deity. Tirupathi is the city which is below the hill whereas Tirumala is the set of seven hills on top of which is situated the temple of Lord Venkateswara Swamy.This temple was constructed centuries ago and attracts a huge number of visitors all over the world. Lord Venkateswara Swamy is addressed with a lot of names such as Balaji, Govinda, Perumaal, Srinivasa etc. The names of these seven hills are Vrushabhadri, Anjanadri, Neelaadri, Garudadri, Seshaadri, Narayanadri and Venkatadri, where Adri means ... Read More

The character of Rapunzel is actually derived from a German fairy tale which is from a collection by Grimm brothers. This was so popular that an idiom “Rapunzel, Rapunzel let down your hair” was made after this story. The character of Rapunzel was discussed in the Disney movie Tangled. She is a young lady having long hair with mysterious powers.The Story of RapunzelThere was an evil witch named Dame Gothel who used to have a walled garden in her premises with Rapunzel plants all over. There lived a couple at her next door who were longing to have children. After ... Read More