List of top Physics Questions on Resistance asked in WBJEE

In an experiment on a circuit, as shown in the figure, the voltmeter shows 8V reading. The resistance of the voltmeter is 
the voltmeter shows 8V reading
A battery of emf E and internal resistance r is connected with an external resistance R as shown in figure. The battery will act as a constant voltage source if:
A battery of emf E and internal resistance r
The current flowing through the 3$\Omega$ resistor in the circuit is,
A micro-ammeter gives full scale deflection at 100 $\mu$A. Its resistance is 2k$\Omega$. The resistance required to convert it to a voltmeter reading 1V is