Embibe Experts Solutions for Chapter: Current Electricity, Exercise 2: Level 2

A copper wire of length $2 \mathrm{m}$ and radius $0.1 \mathrm{cm}$ is joined in series with an iron wire of length $4 \mathrm{m}$ and radius $0.4 \mathrm{cm}$ and a current is passed through the wires. The value of ratio of the current density in iron and copper wires is

A wire has a resistance of $2.5\mathrm{ }\mathrm{\Omega }$ at $28 °\mathrm{C}$ and a resistance of $2.9\mathrm{ }\mathrm{\Omega }$ at $100 °\mathrm{C}$. If the temperature coefficient of resistance of the material of the wire is $\frac{1}{n}°{\mathrm{C}}^{-1}$, then what is the value of $n$?

Brown, Red and Orange coloured bands on a Carbon resistor are followed by silver band. The value of resistor is ________.

An ideal cell of emf $10 \mathrm{V}$ is connected in circuit shown in figure. Each resistance is $2 \mathrm{\Omega }.$ The potential difference (in $\mathrm{V}$) across the capacitor when it is fully charged is ______.

The current through $12 \mathrm{\Omega }$ resistance is zero. The value of $E$ (in Volt) is :

Calculate ratio of $\left(i_1+i_2\right)$ and $i_3$ in following diagram. If the ratio is $\frac{x}{6}$, what is the value of $x?$

The reading of a high resistance voltmeter, when a cell is connected across it is $2.2 \mathrm{V}$. When the terminals of the cell are also connected to a resistance of $5 \mathrm{\Omega }$  as shown in the circuit, the voltmeter reading drops to $1.8 \mathrm{V}$. The internal resistance of the cell is:

Reading of ammeter is $2A$. Find value of $R$ (in $W$) .