The equivalent resistance of the circuit shown below between points a and b is :

The equivalent resistance between A and B as shown in figure is:

Figure shows a part of an electric circuit. The potentials at points $$a, b$$ and $$c$$ are $$30 \mathrm{~V}, 12 \mathrm{~V}$$ and $$2 \mathrm{~V}$$ respectively. The current through the $$20 ~\Omega$$ resistor will be,

A student is provided with a variable voltage source $$\mathrm{V}$$, a test resistor $$R_{T}=10 ~\Omega$$, two identical galvanometers $$G_{1}$$ and $$G_{2}$$ and two additional resistors, $$R_{1}=10 ~M \Omega$$ and $$R_{2}=0.001 ~\Omega$$. For conducting an experiment to verify ohm's law, the most suitable circuit is: