Practice MCQ Questions and answers on Technology-GK

Amplitude modulation was the first type to be used in radio. It works well with HF and morse code.

The terminals of FETs are called gate, drain and source. You might be more familiar with bipolar junction transistors (BJTs), which have terminals called base, collector and emitter. FETs were conceptualized first, but BJTs were easier to produce and so developed sooner.

The first laser was a solid state laser. Solid state refers to any solid material like a glass rod. Diode lasers are very common because they are used to read compact disks and digital video disks in computers, CD players, and DVD players. Before diode lasers, the most common type of laser may have been the helium-neon laser, in which the active medium is a combination of the two gasses helium and neon.

UPS stands for Uninterruptible Power Supply. Examples of equipment that may require a UPS supply are computers, fire detection systems, hospital operating theatre equipment and escape route lighting.