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

For an $\mathrm{AC}$ given by $I=50\cos \left(100t+45°\right) \mathrm{A}$. The value of $I_{\mathrm{rms}}= \_\_\_\_\_\_\_\_\_ \mathrm{A}$.

An $\mathrm{A}.\mathrm{C}.$ voltage $V=5\cos \left(1000t\right) \mathrm{V}$ is applied to a $L-R$ series circuit of inductance $3 \mathrm{mH}$ and resistance $4 \mathrm{\Omega }.$ The value of maximum current in the circuit is _____ $\mathrm{A}$.

If the mains voltage is $230 \mathrm{V}$, then the peak voltage approximately is

A transformer has efficiency $80\%$. It works at $5 \mathrm{kW}$ and $150 \mathrm{V}$. If the secondary voltage is $240 \mathrm{V}$, the secondary current is

A primary coil is connected with an $AC$ source and a bulb is connected with the secondary coil. The voltage across the bulb is $6.0 \mathrm{V}$ and the current through the bulb is $0.4 \mathrm{A}$, The turns ratio is $5:1( \mathrm{Np}:\mathrm{Ns}=5:1)$. Calculate the current in the primary coil.

How much current is drawn by the primary coil of a transformer, which steps down $220 \mathrm{V}$ to $55 \mathrm{V}$ to operate a device with an impedance of $275\mathrm{\Omega }?$

A transformer is used to glow a $140 \mathrm{W}-240 \mathrm{V}$ bulb at $240 \mathrm{V}$ AC. If current in the primary coil is $0.7 \mathrm{A}$, then the efficiency of the transformer is

A transformer is employed to