While travelling on highways during night, one thing you might have noticed that the signboards along the highways are almost always visible. Moreover they appear to glow as your vehicle approaches the signboards. Have you wondered what might have caused these signboards to glow during night? Surely there is some kind of reflection of light … Read more
What is Periscope? A periscope is an optical instrument which is used to see objects that are not in the direct line of sight of observer. It is commonly used in such areas or places where the viewer is hidden or protected such as in submarines to observe surface above water. Working Principle Periscope works … Read more
What is a solenoid? A solenoid is a type of electromagnet which consists of coil of wire in a helical shape. It becomes a magnet when electric current pass through it. Usually, a movable metallic core, of ferromagnetic material such as iron is inserted into this helical coil. The magnetic field of this helical coil … Read more
A solar lighter works by concentrating the sunlight to create enough heat to ignite a combustible material. How it works? The working of solar lighter is as follows: 1. Reflective or Focusing Surface Solar lighters use a parabolic mirror (often made of metal) to focus sunlight into a single, intense point. The mirror has concave … Read more