Photometry and PhotometerThe measurement of light's brightness or luminous intensity is known as photometry. Photometry focuses on the perceived brightness to the human eyes. The photometry takes into account the eye's sensitivity to varying degrees of light and focuses primarily on the visible light spectrum.Thus, the photometry involves the measurement ... Read More

Spot WeldingThe welding process which is used for welding two or more metal sheets together by applying pressure and heat from an electric current to the weld area is known as spot welding.Spot welding is a type of resistance welding process, which is why it is also known as the ... Read More

Seam WeldingThe welding process in which two similar or dissimilar materials are joined at the seam by the application of heat generated from electrical resistance is known as seam welding. The seam welding is a types of resistance welding, in which weld is produced by roller electrodes instead of tipped ... Read More

Polar CurvesThe plots drawn between the candle power and angular position are known as polar curves. Due to unsymmetrical shape of the lamps, the luminous intensity is not uniform in all directions. The luminous intensity in all directions can be represented with the help of polar curves.The polar curves are ... Read More

Laser Beam Welding (LBW) is a fusion welding process in which multiple pieces of metal are joined together through the use of laser. In LBW, the laser beam acts as a concentrated source of heat, which allows narrow, deep welds and high welding rates. The laser beam welding process is ... Read More

The light received by any surface depends upon the angle made by the normal to the surface, to the light flux. The Lambert's cosine law of illumination explains the relation between the illumination of the surface and the cosine of the angle.StatementThe Lambert's cosine law of illumination states that"The illumination ... Read More

Flash WeldingFlash welding, also called flash butt welding, is a resistance welding process, in which the ends of the workpieces are pressed together and a heavy electric current is passed through the joint during the welding process.In flash welding, the electrical current is applied to the workpieces before they are ... Read More

What is Electrolysis?The process of electrolysis can be defined in many ways −A technique that uses a direct electric current to stimulate a non-spontaneous chemical reaction is known as electrolysis.In other words, the process in which ionic substances are decomposed into simple substances by passing an electric current through them ... Read More

A low-pressure mercury vapor gas discharge lamp that uses fluorescence effect to produce visible light is known as fluorescent lamp or fluorescent tube.There are some common faults in case of the fluorescent lamps. These faults, their reasons and treatment methods are described in the following table −Type of FaultReasons of ... Read More

What is Butt Welding?Butt welding is one of the simplest and versatile resistance welding process. In the butt welding process, heat is produced by the contact resistance between two metal workpieces. The faces of the workpieces should be machined or edge prepared.The circuit diagram for butt welding process is shown ... Read More