The AC generator shown in the figure supplies 170 V (max) at 60 Hz. With the switch open as in the diagram, the resulting current leads the generator emf by . With the switch in position 1 the current lags the generator emf by . When the switch is in position 2 the maximum current is 2.82 A. We have to find the values of R, L, and C.

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Let the AC emf and the current in the circuit be described by the functions

The phase angle is given in terms of the values of the circuit components R, L, and C, and the angular frequency by the relation

With the switch open as in the diagram, the resulting current leads the generator emf by . Therefore,

It is given that when the switch in position 1 the current lags the generator emf by . Therefore,

The additional data is that when the switch is in position 2 the maximum current is 2.82 A. This implies that

From equations (C) and (A), we find the value of the resistance R. We find

Substituting the value of R in (B), we get

Substituting the value of R in (A), we get

And,