A galvanometer of resistance $$50 \Omega$$ is connected to a battery $$3 \mathrm{~V}$$ along with a resistance $$2950 \Omega$$ in series. A full scale deflection of 30 divisions is obtained in the galvanometer. In order to reduce this deflection to 20 divisions, the resistance in series should be

If voltage across a bulb rated $$220 \mathrm{~V}, 100 \mathrm{~W}$$ drops by $$2.5 \%$$ of its rated value, then the percentage of the rated value by which the power would decrease is

A wire of resistance $$3 \Omega$$ is stretched to twice its original length. The resistance of the new wire will be

In the given arrangement of experiment on meter bridge, if $$A D$$ corresponding to null deflection of the galvanometer is $$X$$, what would be its value if the radius of the wire $$A B$$ is doubled?