A series L C R circuit is connected to an ac source of variable frequency. When the frequency is increased continuously, starting from a small value, the power factor

Question

A series L C R circuit is connected to an ac source of variable frequency. When the frequency is increased continuously, starting from a small value, the power factor (A) goes on increasing continuously (B) goes on decreasing continuously (C) becomes maximum at a particular frequency (D) remains constant

Tardigrade Admin · Accepted Answer

cos φ=(R/2) when 2=R, i.e at resonance cos φ =is max ( when Z) is max ∴ max at a particular frequency

Q. A series $L CR$ circuit is connected to an ac source of variable frequency. When the frequency is increased continuously, starting from a small value, the power factor

goes on increasing continuously

goes on decreasing continuously

becomes maximum at a particular frequency

remains constant

$cos ϕ = \frac{R}{2}$
when $2 = R$ , i.e at resonance
$cos ϕ$ =is max ( when $Z$ ) is max
$∴$ max at a particular frequency

Q. A series LCR circuit is connected to an ac source of variable frequency. When the frequency is increased continuously, starting from a small value, the power factor