AIPMT-MAINS Physics Current Electricity Class 12 Questions

The power dissipated in the circuit shown in the figure is 30 Watts. The value of R is:

Cell having an emf ε and internal resistance r is connected across a variable external resistance R. As the resistance R is increased, the plot of potential difference V across R is given by:

A galvanometer of resistance, G is shunted by a resistance S Ω. To keep the main current in the circuit unchanged, the resistance to be put in series with the galvanometer is

See the electric circuit shown in this Figure. Which of the following equations is a correct equation for it?

A wire of resistance 12 Ω per meter is bent to form a complete circle of radius 10 cm. The resistance between its two diametrically opposite points, A and B as shown in the Figure, is:

A galvanometer having a coil resistance of 60 Ω shows full scale deflection when a current of 1.0 amp passes through it. It can be converted into an ammeter to read currents up to 5.0 amp by:

A student measures the terminal potential difference (V) of a cell (of emf ε and internal resistance r) as a function of the current (I) flowing through it. The slope, and intercept, of the graph between V and I, then, respectively, equal:

The mean free path of electrons in a metal is 4 × 10⁻⁸ m. The electric field which can give on an average 2 eV energy to an electron in the metal will be in units of V/m: