Multiple Choice
In residential electrical power systems (homes), which type of current is supplied by the utility to wall outlets?
2
views
31. Alternating Current
Alternating Voltages and Currents
Struggling with Physics?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
The current in an AC circuit takes 0.02 s to change direction. What is the angular frequency of the AC source?
A
6.4×10−3 s−1
B
0.04 s−1
C
0.25 s−1
D
157 s−1
Verified step by step guidance1
Understand that the time given, 0.02 s, is the time taken for the current to change direction, which corresponds to half of the period of the AC cycle.
The full period (T) of the AC cycle is twice the time taken for the current to change direction, so T = 2 * 0.02 s = 0.04 s.
Recall the relationship between angular frequency (ω) and period (T): ω = 2π / T.
Substitute the value of the period into the formula: ω = 2π / 0.04 s.
Calculate the angular frequency using the formula, which will give you the correct answer of 157 s⁻¹.
7:49mWatch next
Master Alternating Voltages and Currents with a bite sized video explanation from Patrick
Start learningRelated Videos
Related Practice
Alternating Voltages and Currents practice set
Problem sets built by lead tutorsExpert video explanations