Question
Download Solution PDFA sinusoidal alternating voltage of time period 36 ms has the maximum value of 250 V. Its value will reach -125 V (half the value of negative maximum) after ______ milliseconds.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFConcept
A sinusoidal voltage can be expressed as:
\(v(t)=V_msin(ω t+ϕ)\)
where, Vm = Maximum value of input voltage
\(\omega={2\pi \over T}=\) Angular frequency
ϕ = Phase difference
T = Time period
Calculation
Given, Vm = 250 V
T = 36 ms
\(\omega={2\pi \over 36\times 10^{-3}}rad/s\)
\(-125=250sin(ω t)\)
\(\omega t={7\pi\over 6}\)
\(t={7\pi\over \omega}={7\pi\times 36\times 10^{3}\over 6\times 2\pi}\)
t = 21 ms
Mistake Points Remember that time should be always positive that's why sin-1(-0.5) = 7\(\pi \)/6 instead of \(\pi \)/6.
Last updated on May 29, 2025
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