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The potential difference V across and th...

The potential difference `V` across and the current `I` flowing through an instrument in an `AC` circuit are given by:
`V=5 cos omega t` volt
`I=2 sin omega t` Amp.

A

Zero

B

5 watt

C

10 watt

D

`2.5` watt

Text Solution

Verified by Experts

`P _(av) = v _(rms) I _(rms) cos phi`
Here `phi = 90^(@) so P _(av) = 0`
`phi = 90 ^(@) P _(av) = 0`
Alter. `v = 5 cos (omega t )`
`i = 2 sin omega t `
`P v _(rms) I _(rms) .cos phi`
`phi = 90^(@)`
`implies P = 0`
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