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

State Joule's law of heating.

Derive the expression for power $P=V\times I$, in an electrical circuit.

In the Fig., what is the potential difference $V_d-V_c$ between the points $d$ and $c$ if ${\mathcal{E}}_1=4.0 \mathrm{V}, {\mathcal{E}}_2=1.0 \mathrm{V}, R_1=R_2=10 \mathrm{\Omega },$ and$R_3=8.0 \mathrm{\Omega }$ and the battery is ideal?

$\mathrm{n}$ identical cells, each of emf E and internal resistance $\mathrm{r}$, are connected in series to a resistor $\mathrm{R}$. Deduce an expression for the internal resistance $\mathrm{r}$ of one cell in terms of the current $\mathrm{I}$ in the circuit.

Find the emf of the battery shown in figure.

Find the emf and the internal resistance of an electric source which is equivalent to two batteries of emf's $E_1$ and $E_2$ and internal resistances $r_1$ and $r_2$ connected in parallel.

Prove that two identical cells (each of emf $E$, internal resistance $r$) will send same current in an external resistance $R$ whether all cells are connected in series or in parallel, if $R=r$.

Two cells, each of emf $1.5 \mathrm{V}$ are joined in series and send $1.0 \mathrm{A}$ current in an external resistor. If the same cells are joined in parallel, then they send $0.6 \mathrm{A}$ current in the same resistor. What is the internal resistance of each cell?