1.A voltage transformer of which class of accuracy can be used for precision testing in standard laboratories? (a) 0.1 class (b) 10 class (c) 5.00 class (d) 1000 class 2. In a transformer the tappings are generally provided on (a) primary side (b) secondary side (c) low voltage side (d) high voltage side 3. The […]
1. In a 50 kVA transformer the number of turns in the primary and secondary windings are 834 and 58 respectively. If the primary is connected to 3300 V supply the secondary current will be (a) 15 A (b) 30 A (c) 218 A (d) 238 A 2. If full load copper loss of a
1. In a power transformer (a) primary winding is closer to core (b) secondary winding is closer to core (c) low voltage winding is closer to core (d) high voltage winding is closer to core 2. In a transformer, the magnetic coupling between primary and secondary circuit can be increased by (a) increasing the number
A current limiting reactor is a coil which has a large inductive reactance in comparison with its ohmic resistance. It consists of a few turns of heavy copper strip, sometimes cast directly in concrete so that it can withstand large stress developed by the fault currents. Generally, the reactance of the power system under fault
There are two types of extrinsic semiconductors. These are n-type and p-type. In n-type, the electrons are majority charge carriers while holes are minority charge carriers. In p-type, the holes are majority charge carriers and electrons are minority charge carriers. When these two types of materials namely n-type and p-type are chemically combined with a special
A fuel cell is defined as an electrochemical device that continuously converts the chemical energy of fuel into electricity and heat without combustion. Difference between Fuel Cell and Battery: A fuel cell is similar to other electrical cells (battery) in respect that both have the positive and negative electrodes with an electrolyte between them and
Following are the most common types of fuel cell Types of Fuel Cell Important fuel cell types are described here except the alkaline fuel cell (AFC) as it is discussed earlier. Phosphoric Acid Fuel Cells (PAFC) A schematic diagram of phosphoric acid fuel cell is shown in Figure. It was developed in 1980s. It uses
Fuel cell technology is the new emerging technology. The development of this technology has started only few decades back and it is still under development for its commercial and economical use. In this article, I am going to explain the working principle of fuel cell. Working Principle of Fuel Cell A fuel cell is an
A resonance circuit consists of a capacitor and an inductor. It also has some resistance. Either this resistance may be the effective resistance of the coil itself or connected externally to create some desired effect. A resonance RLC series circuit is shown in Figure. Here, a capacitor C and an inductor L are connected
Wheatstone Bridge Working Principle Wheatstone devised a bridge-arrangement of resistances by which the resistance of a given conductor can be determined. This arrangement is called the ‘Wheatstone bridge‘. In the arrangement, four resistances are so connected as to form a parallelogram. In one diagonal of this parallelogram is connected a galvanometer and in