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

For the three values of resistances $R$ namely $R_1, R_2$ and $R_3$ the balanced positions of a jockey are at $A, B$ and $C$, respectively. Which position will show the most accurate result for calculation of $X$. Give reason. $B$ is near the mid-point of the wire.

In the post office box circuit, $10 \mathrm{\Omega }$ plug is taken out in arm $AB$ and $100 \mathrm{\Omega }$ plug is taken out in arm $BC$. If the unknown resistor is kept in melting ice chamber, $600 \mathrm{\Omega }$ resistance is required in arm $AD$ for zero deflection in the galvanometer. Now if the unknown resistor is kept at $100° \mathrm{C}$ (steam chamber), $630 \mathrm{\Omega }$ resistance is required in arm $AD$ for zero deflection. Temperature coefficient of resistance of the unknown wire is:

In the meter bridge circuit, the point $D$ is the balance point.

In the circuit shown find

$\left(\mathrm{a}\right)$ the power drawn from the cell,

$\left(\mathrm{b}\right)$ the power consumed by the resistor which is converted into heat and

$\left(\mathrm{c}\right)$ the power given to the inductor.

Find the current flowing through the resistance $R_1$ of the circuit shown in figure if the resistances are equal to $R_1=10 \mathrm{\Omega }, R_2=20 \mathrm{\Omega }$, and $R_3=30 \mathrm{\Omega }$, and the potentials of points $1, 2$ and $3$ are equal to ${\mathrm{\phi }}_1 = 10 \mathrm{V}, {\mathrm{\phi }}_2 = 6 \mathrm{V},$ and ${\mathrm{\phi }}_3 = 5 \mathrm{V}$.

In the circuit shown in figure if the resistances are equal to $R_1=10 \mathrm{\Omega }, R_2=20 \mathrm{\Omega }$, and $R_3=30 \mathrm{\Omega }$, and the potentials of points $1, 2$ and $3$ are equal to ${\mathrm{\phi }}_1 = 10 \mathrm{V}, {\mathrm{\phi }}_2 = 6 \mathrm{V},$ and ${\mathrm{\phi }}_3 = 5 \mathrm{V}$.

A battery of internal resistance $4 \mathrm{ohm}$ is connected to the network of resistance as shown. In the order that the maximum power can be delivered to the network, the value of $R$ in $\mathrm{ohm}$ should be :

In these three circuits all the batteries are identical and have negligible internal resistance, and all the light bulbs are identical. Rank all $5$ light bulbs $(A\mathit{,}\mathit{ }B\mathit{,}\mathit{ }C\mathit{,}\mathit{ }D\mathit{,}\mathit{ }E)$ in order of brightness from brightest to dimmest.