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Question
An alternative voltage given by V = 140 sin 314t is connected across a pure resistor of 50 Ω. Find
- The frequency of the source.
- The rms current is through the resistor.
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Solution
Given:
V = 140 sin 314t, R = 50Ω
- Comparing with V = V0 sinωt
Thus, V0 = 140 V
ω = 314
2πν = 314
`"ν" = 314/(2 xx3.14) "Hz" = 50" Hz"` - `"V"_("rms") = "V"_0/sqrt2 = 140/sqrt2 = 98.99"V"`
`"I"_("rms") = "V"_("rms")/"R" = 98.99/50 = 1.97"A"`
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