$A$ galvanometer of resistance $36 \ \Omega$ is converted into an ammeter by using a shunt of $4 \ \Omega$. The fraction $f_0$ of the total current passing through the galvanometer is:

Given below are two statements:
Statement $I$: If the number of turns in the coil of a moving coil galvanometer is doubled,then the current sensitivity becomes double.
Statement $II$: Increasing the current sensitivity of a moving coil galvanometer by only increasing the number of turns in the coil will also increase its voltage sensitivity in the same ratio.
In the light of the above statements,choose the correct answer from the options given below:

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

$A$ galvanometer of $50 \, \Omega$ resistance has $25$ divisions. $A$ current of $4 \times 10^{-4} \, A$ gives a deflection of one division. To convert this galvanometer into a voltmeter having a range of $25 \, V$, it should be connected with a resistance of

An ideal ammeter and an ideal voltmeter have resistances of . . . . . . $\Omega$ and . . . . . . $\Omega$ respectively.

$A$ galvanometer has a resistance of $20\,\Omega$ and reads full-scale when $0.2\,V$ is applied across it. To convert it into a $10\,A$ ammeter,the galvanometer coil should have a