S. L. Arora Solutions for Chapter: Alternating Current and Electrical Machines, Exercise 1: Problems For Practice

The emf of an a.c source is given by the expression $\epsilon =300 \sin 314t$. Write the value of peak voltage and frequency of the source.

The instantaneous current from an a.c. source is $I=5\sin 314t$. What is the rms value of current in ampere? (Write the answer up to two significant figure.)

An alternating voltage given by $V=140 \sin 314t$ is connected across a pure resistor of $50\mathrm{\Omega }$.

Find (i) the frequency of the source. (ii) the rms current through the resistor.

An alternating emf of peak value $350\mathrm{}\mathrm{V}$ is applied across an a.c. ammeter of resistance $100\mathrm{}\mathrm{\Omega }$. What is the reading of the ammeter in ampere up to two significant digit?

The effective value of current in a $50$ cycle a.c. circuit is $5\mathrm{A}$. Magnitude of current is $n.123 \mathrm{A}$, $1/300$ seconds after it was zero. Find the value of $n$.

The peak value an alternating current of frequency $50\mathrm{}\mathrm{H}\mathrm{z}$ is $14.14\mathrm{}\mathrm{A}.$ Find its rms value. How much time will the current take in reaching from $0$ to maximum value?

$100\mathrm{\Omega }$ iron is connected to a $220\mathrm{}\mathrm{V},\mathrm{}50$ cycles wall plug. What is (i) peak potential difference (ii) average potential difference and (iii) rms current?

The equation of a.c in a circuit is $I=50\sin 100\pi t.$ Find (i) frequency of a.c., (ii) mean value of a.c. over positive half cycle, (iii) rms value of current and (iv) the value of current $1/300$ second after it was zero.