Embibe Experts Solutions for Chapter: Alternating Current, Exercise 1: Exercise-1

An alternating current flows through a circuit consisting of inductance $L$ and resistance $R$. Periodicity of the supply is $\frac{\omega }{2\pi }$. which of the following is true?

In following diagram voltage on $L$ and $C$ is-

An $LCR$ series circuit is connected to a source of alternating current. At resonance, the applied voltage and the current flowing through the circuit will have a phase difference of-

For an A.C. circuit at the condition of resonance-

At a frequency more than the resonance frequency, the nature of an anti-resonant circuit is-

If resonance frequency is $f$ and then the capacity is increased $4$ times, then new resonance frequency becomes-

In a transformer, number of tums in the primary are $140$ and that in the secondary are $280$. If current in primary is $4 \mathrm{A}$, then that in the secondary is : (assume that the transformer is ideal)

A transformer is used for a $100 \mathrm{watt}$, $20 \mathrm{volt}$ electric bulb at a place where the A.C. mains potential is $200 \mathrm{volt}$ and the current drawn is $0.6 \mathrm{A}$. The efficiency of the transformer is nearly