A 0 - 10mA galvanometer with a coil resistance of 30Ω$\Omega $ can be converted to a 0 - 10A ammeter by using

Answer Details

To convert the galvanometer into an ammeter, a shunt resistor needs to be connected in parallel with the galvanometer. This allows only a fraction of the current to pass through the galvanometer, while the rest of the current flows through the shunt resistor.
Using Ohm's Law, the resistance of the shunt resistor can be calculated. The formula for the shunt resistance is:
Rs = G * Rg / (Imax - G)
where Rs is the shunt resistance, Rg is the coil resistance of the galvanometer, Imax is the maximum current that the ammeter can measure (in this case, 10A), and G is the sensitivity of the galvanometer (in this case, 10mA).
Substituting the values given in the question, we get:
Rs = 0.01 * 30 / (10 - 0.01) = 0.03 Ω
Therefore, the correct answer is a 0.03Ω shunt resistor.