AC Frequency: Calculating from V, I, & t

Click For Summary
SUMMARY

The frequency of the alternating current (AC) in the given circuit can be directly calculated from the equation I = (0.669 A) sin [(491 Hz)t]. The term 491 Hz represents the angular frequency, which is related to the frequency by the formula f = ω/(2π). Thus, the frequency of the AC is 491 Hz / (2π) = 78.2 Hz. This calculation confirms that the light bulb operates at a frequency of 78.2 Hz, derived from the sine function's properties.

PREREQUISITES
  • Understanding of AC circuit fundamentals
  • Familiarity with trigonometric functions and their properties
  • Knowledge of angular frequency and its relation to frequency
  • Basic algebra for manipulating equations
NEXT STEPS
  • Study the relationship between angular frequency and frequency in AC circuits
  • Learn about the characteristics of sine and cosine functions in electrical engineering
  • Explore practical applications of AC frequency calculations in circuit design
  • Investigate the effects of frequency on electrical components like light bulbs
USEFUL FOR

Students in physics or electrical engineering, educators teaching AC circuit concepts, and anyone interested in understanding the mathematical relationships in alternating current systems.

arod2812
Messages
25
Reaction score
0

Homework Statement


A light bulb is connected to a 120.0-V wall socket. The current in the bulb depends on the time t according to the relation I = (0.669 A) sin [(491 Hz)t].

What is the frequency of the alternating current?


Homework Equations


How do I use the given value for I?? (since it includes time, t)


The Attempt at a Solution


I know that V=Vo * sin2pi * freq * time
 
Physics news on Phys.org
The only relevant equation you should be using is:

sin(kt)

Suppose I have the equation sin(pi*x), can you tell me what the period of this function is? Can you tell me the frequency? Draw it out. Now if I tell you I have the equation sin(491*x), can you tell me the same information?

You will notice a pattern such as: sin(k*x) -> sin(2*pi*f*x) in terms of frequency.
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 8 ·
Replies
8
Views
3K
Replies
30
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 7 ·
Replies
7
Views
4K