Suppose there is a circuit consisting of only resistances and batteries. Suppose one is to double (or increase it to n times) all voltages and resistiances. Show that currents are unaltered.

Four identical cells each of emf 2V, are joined in parallel providing supply of current to external circuit consisting of two 15 Omega resistors joined in parallel. The terminal voltage of the cells ae read by an ideal voltmeter is 1.6V. Calculate the internal resistance of each cell.

Four identical cells each of emf 2V, are joined in parallel providing supply of current to external circuit consisting of two 5 Omega resistors joined in parallel. The terminal voltage of the cells ae read by an ideal voltmeter is 1.6V. Calculate the internal resistance of each cell.

If the current sensitivity of a moving coil galvanometer is increased by 20%, it resistance also increases by 1.5 times. How will the voltage sensitivity of the galvanometer be affected?

For a CE-transistor amplifier, the audio signal voltage across the collected resistance of 2 k omega is 2 V. Suppose the current amplificationfactor of the transistor is 100, find the input signal voltage nd base current, if the base resistance is 1 k omega .

n cells of e.m.f E and internal resistance r are connected in series with an external resistance R . the current will increase n times that of a single cell, if

Show mathematically that in an a.c. circuit containing only inductance, the current lags behind the e.m.f. by a phase of pi/2 . An a.c. voltage E=E_0 sin omegat is applied across an inductor L. Obtain an expression for current I.

A battery of emf 10 V and internal resistance 3 Omega is connected to a resistor. If the current in the circuit is 0.5 A, what is the resistance of the resistor? What is the terminal voltage of the battery when the circuit is closed?

First a set of n equal resistors of R each are connected in series to a battery of emf E and internal resistance R. A current I is observed to flow. Then, the n resistors are connected in parallel to the same battery. It is observed that the current is increased 10 times. What is 'n'?

The following circuit shows the use of potentionmeter to measure the internal resistance of a cell.When the key K is closed, how does the balance point change if R is increased keeping current from the driver cell constant?