Current Electri...

A potentiometer wire of length $$L$$ and resistance $$10\Omega$$ is connected in series with a battery of e.m.f. $$2.5\ V$$ and a resistance in its primary circuit. The null point corresponding to a cell of e.m.f. $$1\ V$$ is obtained at a distance $$L/2$$. If the resistance in the primary circuit is doubled then the position of new null point will be

The total electrical resistance between the points $$A$$ and $$B$$ of the circuit shown is:

If specific resistance of a potentiometer wire is $$10^{-7}\Omega m$$ and current flowing through it is $$0.1\ amp$$., cross-sectional area of wire is $$10^{-6}m^{2}$$ then potential gradient will be

A potentiometer wire of length $$1m$$ has a resistance of $$100\Omega $$. It is connected in series with a resistance and a battery of emf $$2V$$ of negligible resistance. A source of emf $$10mV$$ is balanced against a length of $$40cm$$ of the potentiometer wire. What is the value of the external resistance.

Two coils have a combined resistance of $$12 \Omega$$, when combined series and $$5/3 \Omega$$, when connected in parallel. Their respective resistances are:

Ravi connected three bulbs with the cells and a switch as shown. When switch is moved to ON position.

Which of the following circuit diagram represents the given torch?

Which of the following I-V graph represents ohmic conductors?

In parallel combination of n cells, we obtain:

What is the value of unknown resistance R, of galvanometer shows null deflection in the given meter bridge set up shown in the fig?