A variable reluctance tachometer has 180 teeth on its rotor. The speed of the shaft on which it is mounted is 1200 r.p.m. The frequency of the output pulses is

This question was previously asked in
ESE Electronics 2018: Official Paper
View all UPSC IES Papers >
  1. 4800 / s
  2. 3600 / s
  3. 2400 / s
  4. 1800 / s

Answer (Detailed Solution Below)

Option 2 : 3600 / s
Free
ST 1: UPSC ESE (IES) Civil - Building Materials
6.2 K Users
20 Questions 40 Marks 24 Mins

Detailed Solution

Download Solution PDF

Concept:

In variable reluctance tachometer,

Frequency of output pulse = (No. of teeth on the rotor) × (speed of shaft).

Calculation:

Given:

No. of teeth = 180, speed = 1200 rpm

So, the frequency of the output pulse will be:

\(= \frac{{\left( {180 \times 1200} \right)}}{{minute}}\)

\( = \left( {\frac{{180 \times 1200}}{{60}}} \right)/sec\)

= 3600/sec

Latest UPSC IES Updates

Last updated on May 28, 2025

->  UPSC ESE admit card 2025 for the prelims exam has been released. 

-> The UPSC IES Prelims 2025 will be held on 8th June 2025.

-> The selection process includes a Prelims and a Mains Examination, followed by a Personality Test/Interview.

-> Candidates should attempt the UPSC IES mock tests to increase their efficiency. The UPSC IES previous year papers can be downloaded here.

Get Free Access Now
Hot Links: teen patti gold download apk teen patti customer care number teen patti wealth