The potential difference between points $A$ and $B$ is

   

Find the current through the $10 \mathrm{\Omega }$ resistor shown in figure

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

Figure shows a circuit that may be used to compare the resistance $R$ of an unknown resistor with a $100 \mathrm{\Omega }$ standard. The distances $l$ from one end of the potentiometer slider wire to the balance point are $400 \mathrm{m}\mathrm{m}$ and $588 \mathrm{m}\mathrm{m}$ when $X$ is connected to $Y$ and $Z$, respectively. The length of the slide wire is $1.00 \mathrm{m}$. What is the value of resistance $R$?

In the circuit shown in the figure, an ideal ammeter and an ideal voltmeter are used. When the key is open, the voltmeter reads $1.53 \mathrm{V}$. When the key is closed, the ammeter reads $1.0 \mathrm{A}$ and the voltmeter reads $1.03 \mathrm{V}$. The resistance $R$ is