Physics

Electrical Machines and Circuits

754 Questions

Electrical machines and circuits involve the principles of alternating and direct current, transformers, diodes, and power consumption. These concepts are essential for engineering and technical exams. Review these practice questions to test your knowledge of circuit analysis.

Transformers and impedanceAlternating and direct currentCircuit components and diodesPower consumption calculations

Electrical Machines and Circuits Questions

Multiple choice technology

Transformer stage can have how many input links ,output links and reject links ?

  1. a) 2 input links,3 output links and 2 reject links

  2. b) 1 input link,any number of output links and 1 reject link.

  3. c) 1 input link,3 output links and 1 reject link.

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Transformer stage in DataStage accepts one input link, can have any number of output links for routing transformed data, and has one reject link for capturing records that fail transformation rules. This design allows flexible data transformation with multiple output destinations and error handling.

Multiple choice

Which cable is utilised to get power from main socket?

  1. Power cable

  2. Signal cable

  3. AC cable

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The power cable connects electronic devices to the main power socket, supplying the necessary electrical current for operation. Signal cables transmit data signals between devices. AC cables carry alternating current but 'power cable' is the specific common term for the cable from the main socket to the device.

Multiple choice

An ideal op-amp is an ideal

  1. voltage controlled current source

  2. voltage controlled voltage source

  3. current controlled current source

  4. current controlled voltage source
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An ideal OPAMP is an ideal voltage controlled voltage source.

Multiple choice

Voltage series feedback (also called series-shunt feedback) results in

  1. increase in both input and output impedances

  2. decrease in both input and output impedances

  3. increase in input impedance and decrease in output impedance

  4. decrease in input impedance and increase in output impedance
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In voltage series feedback amplifier, input impedance increases by factor $(1+A\beta)$ and output impedance decreases by the factor $(1+A\beta)$

$$R_{if} = R_i(1+A\beta)\\

R_{of} = \dfrac{R_0}{(1+A\beta)} $$

Multiple choice

The effect of current shunt feedback in an amplifier is to

  1. increase the input resistance and decrease the output resistance

  2. increase both input and output resistances

  3. decrease both input and output resistances

  4. decrease the input resistance and increase the output resistance
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The given solution is right.                    Here  Ri  = input resistance without feedback                              Rif  = input resistance with feedback                              R of  = output resistance with feedback