An alternating voltage is given by 30sin157 the frequency of alternating voltage is:
Correct answer: B. 25Hz
- A. 100Hz
- B. 25Hz
- C. 50Hz
- D. 75Hz
Explanation
The equation for the alternating voltage you've provided is in the form of Vt=Vm sin(ωt)where:Vm is the peak voltage, andω is the angular frequency.In your case, Vm =30 and ω=157.The frequency f of the alternating voltage can be found from the angular frequency ω using the relation f=ω/2π Substituting ω=157 into the equation gives: f=157/2π ≈25HzSo, the frequency of the alternating voltage is approximately 25 Hz.
Last updated
About Phase of Alternating Current
Phase describes the position of an alternating voltage or current within its cycle and the phase difference between two sinusoidal quantities. The topic covers in phase signals, phase angle and lead or lag in resistive, inductive and capacitive circuits, rather than the amplitude or frequency of the supply.
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
A phase difference of 90 degrees is equal to:
Alternating current cannot be measured with a moving coil galvanometer directly because
An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ?
An alternating current of the r.m.s value of 4.0 A and frequency 50Hz flows in a circuit containing a 10Ω resistor. The peak current is then ?
If the instantaneous current in a circuit is given by I = A sin (wt) ampere, the RMS value of the current is: