An alternating voltage e = 400 sin 314t is applied to a device that offers an ohmic resistance of 10 Ω to the flow of current in one direction while preventing the flow of current in the opposite direction. Calculate the RMS value and average value, respectively, for the current over one cycle.

This question was previously asked in
PGCIL DT Electrical 13 Aug 2021 Official Paper (NR I)
View all PGCIL Diploma Trainee Papers >
  1. 10 A and 15 A
  2. 15 A and 10 A
  3. 4 A and 7.5 A
  4. 20 A and 12.7 A

Answer (Detailed Solution Below)

Option 4 : 20 A and 12.7 A
Free
PGCI DT EE Power System Mock Test
6.1 K Users
20 Questions 20 Marks 15 Mins

Detailed Solution

Download Solution PDF

Given, e = Em sin ωt = 400 sin 314t

Hence, Em = 400 volts,

The device offers an ohmic resistance (R) of 10 Ω

Hence, the maximum value of current (Im) is, \(\dfrac{E_m}{R}=\dfrac{400}{10} = 40\ A\) .... (1)

Since, the flow of current in one direction, while preventing the flow of current in the opposite direction, hence resultant waveform from actual waveform can be drawn as,

611b7a7cedd65efe009688e1 16309420995311

Since, the resultant waveform looks like the output waveform of the Half-Wave Rectifier,

For Half Wave Rectifier,

RMS Value = \(\dfrac{A_m}{2}\) .... (2)

Average Value = \(\dfrac{A_m}{\pi}\) .... (3)

Where, Am is the maximum value of an alternating quantity,

From equation (1),

Am = Im = 40 A

From equations (2) and, (3),

RMS Value of current = \(\dfrac{40}{2}=20\ A\)

Average Value of current = \(\dfrac{40}{\pi}=12.7\ A\)

Latest PGCIL Diploma Trainee Updates

Last updated on May 9, 2025

-> PGCIL Diploma Trainee result 2025 will be released in the third week of May. 

-> The PGCIL Diploma Trainee Answer key 2025 has been released on 12th April. Candidates can raise objection from 12 April to 14 April 2025.

-> The PGCIL DT Exam was conducted on 11 April 2025. 

-> Candidates had applied online from 21st October 2024 to 19th November 2024.

-> A total of 666 vacancies have been released.

-> Candidates between 18 -27 years of age, with a diploma in the concerned stream are eligible.

-> Attempt PGCIL Diploma Trainee Previous Year Papers for good preparation.

More Diodes and Its Applications Questions

Get Free Access Now
Hot Links: teen patti tiger teen patti stars teen patti download teen patti go teen patti sequence