1) In pure inductive circuit current a) lags behind emf by π/2 b) lags behind emf by π 2) The phase difference between voltage and current in case of resistor is? a) (a) lags behind emf by π/2 b) (b) leads the emf by π/2 c) in phase 3) The value of inductance reactance is? a) ωC b) ωL c) R 4) The current in the pure capacitor? a) leads the emf by π/2 b) lags behind emf by π c) in phase 5) The impedance value of a pure capacitor is? a) 1/ωC b) ωL c) ωC 6) The number of complete cycles of an alternating current occurring in one second is known as: a) the r.m.s. or effective value b) the peak value of the alternating current c) the frequency of the alternating current 7) What is the ratio of inductive and capacitance reactances in an ac circuit? a) ω²L b) l c) 1 d) ω²LC 8) What happen to the resistance if frequency double up in AC circuit? a) R become zero b) R remain uncharge c) R become double 9) What happen to the capacitive reactance if frequency double up in AC circuit? a) X𝒸 become half b) X𝒸 become zero c) X𝒸 become double 10) Power dissipates in LCR circuit in : a) L only b) R only c) C only 11) The circuit is said to be in resonance if the current is ____ with the applied voltage. a) in phase b) out of phase 12) As XL = XC in a series resonance circuit, the impedance is_________ a) purely inductive b) purely resistive 13) If the value of C in a series RLC circuit is decreased, the resonant frequency a) constant b) decrease c) increase 14) If the value of inductor,L in a series RLC circuit is increased, the resonant frequency a) decrease b) increase c) constant 15) In a series resonance circuit, series resonance occurs when? (choose which apply) a) Vs out of phase with current, I b) XL = Xc c) Z=R 16) Frequency defined as _____. a) number of complete cycle per unit time b) time taken for one complete cycle 17) The SI unit of Peak Current is _____? a) I b) A c) V d) R

Chapter 6 Alternating Current

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