A galvanometer $(G=1000 \mathrm{\Omega })$ gives full scale deflection when a current $10 \mathrm{\mu A}$ flows through it. It is required to measure a current whose maximum value does not exceed $1 \mathrm{A}$. To do so we need to connect a resistance of

An ammeter is obtained by shunting a $30 \mathrm{\Omega }$ galvanometer with $30 \mathrm{\Omega }$ resistance. What additional shunt be connected across it to double its range?

A galvanometer of resistance $90 \mathrm{\Omega }$ is shunted by a resistance of $10 \mathrm{\Omega }$. What fraction of main current passes through the shunt?

A voltmeter reads $3 \mathrm{V}$ at full-scale deflection and is graded as $6000 \mathrm{\Omega } {\mathrm{V}}^{-1}$. What resistance should be connected in series with it so that it reads $12 \mathrm{V}$ at full scale deflection?

Assertion: The resistance of an ideal voltmeter should be infinite.

Reason: The lower resistance of the voltmeter gives a reading lower than the actual potential difference across its terminals.

A moving coil galvanometer of resistance $40 \Omega$ gives full scale deflection when a current of $0.25 \mathrm{mA}$ is passed through it. To convert it to voltmeter of range $10 \mathrm{V}$, the resistance required to be placed in series is

A galvanometer can withstand safely a maximum current of $5 \mathrm{mA}$. It is converted into a voltmeter reading upto $20 \mathrm{V}$ by connecting in series, an external resistance of $3.96 \mathrm{k} \Omega$ The resistance of the galvanometer is

A galvanometer gives full scale deflection when the current passed through it is $3 \mathrm{mA}$. Its resistance is $100 \Omega$ without connecting additional resistance in series, then it can be used as voltmeter of range

A voltmeter of range $3 \mathrm{V}$ and resistance $200 \Omega$ cannot be converted to an ammeter of range