Important Questions of Power Factor Improvement: 1. Why is there phase difference between voltage and current in an a.c. circuit ? Explain the concept of power factor. 2. Discuss the…
Important Questions of Dynamic Electric: 1. A gear train system used to drive a load is shown in Fig. P2. Assuming the ideal conditions of no back lash and no…
Important Questions of Characteristics of Electric Motors: Problems of Characteristics of Electric Motors: 1.A 50 hp, 220 V, 1200 rpm dc shunt motor has an efficiency of 85% at full…
Thyristors Articles: Silicon Controlled Rectifier Principle Operation: Silicon Controlled Rectifier Principle Operation (SCR) consists of four layers of semiconductor material, alternately p-type and n-type as illustrated in Fig. 19-1(a). Because…
Audio Power Amplifiers Articles: Transformer Coupled Class A Amplifier: Class A Circuit – Instead of capacitor coupling, a Transformer Coupled Class A Amplifier may be used to ac couple amplifier…
Tunnel Diode Operation and Characteristics: Tunnel Diode Operation - A tunnel diode (sometimes called an Esaki diode after its inventor, Leo Esaki) is a two-terminal negative resistance device that can…
Photodarlington Working: The Photodarlington Working shown in (Fig. 20-33) consists of a phototransistor connected in Darlington arrangement with another transistor. This device is capable of producing much higher output currents…
Phototransistor Working: A Phototransistor Working is similar to an ordinary BJT except that its collector base junction is constructed like a photodiode. Instead of a base current, the input to…