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BSElectrician
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Homework Statement
An alternating voltage is given by [tex]v = 30\sin(314t)[/tex].The time taken by the voltage to reach 30V for the first time is:
A. 0.02s
B. 0.03s
C. 0.1s
D. 0.015s
Homework Equations
google for equation for instantaneaous current and voltage
The Attempt at a Solution
30 = 30sin(314t)
1 = sin(314t)
pi/2 = 314t
t = 0.005s
not in the choices
EDIT
30 = 30sin(314t - pi)
pi/2 = (314t - pi)
t = 0.015 from the choices
why do i need to subtract 180 degrees inside the sine eqn instead of adding
( Formula for n repeating cycles is v(t + nT) )
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