Asked in NUMS 2019 (cancelled sitting) 2019Moderate

A cathode ray oscilloscope is displaying an AC signal. If one wave is completed in 2 cm along X- axis and time-base setting is 10 ms/cm, then frequency of AC signal will be:

Correct answer: B. 50 Hz

  • A. 100 Hz
  • B. 50 Hz
  • C. 20 Hz
  • D. 10 Hz
  • E. 200 Hz

Explanation

The distance traveled by the wave along the X-axis in one complete cycle is the wavelength, which is given as 2 cm in the problem. The time-base setting is given as 10 ms/cm, which means that one centimeter along the X-axis represents a time of 10 ms. Therefore, the time taken for one complete cycle is:Time = (2 cm) x (10 ms/cm) = 20 msThe frequency, f, is given by the formula:f = 1/TWhere T is the time taken for one complete cycle. Substituting the value of T, we get:f = 1/20 ms = 50 HzTherefore, the frequency of the AC signal is 50 Hz. The correct answer is B.

Last updated

About AC Through Resistor, Capacitor and Inductor

Alternating current through a resistor, capacitor and inductor involves phase relationships between voltage and current, reactance, impedance and energy transfer. A resistor keeps voltage and current in phase, while a capacitor and inductor produce opposite phase shifts, a distinction used in circuit diagrams and numerical calculations.

Practise Alternating Current

592 free Alternating Current MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Exams that ask Physics questions like this

Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions