JEE MAIN - Physics (2016 (Offline) - No. 10)

A galvanometer having a coil resistance of $$100\,\Omega $$ gives a full scale deflection, when a currect of $$1$$ $$mA$$ is passed through it. The value of the resistance, which can convert this galvanometer into ammeter giving a full scale deflection for a current of $$10$$ $$A,$$ is :
$$0.1\,\Omega $$
$$3\,\Omega $$
$$0.01\,\Omega $$
$$2\,\Omega $$

Explanation

$${\rm I}gG = \left( {{\rm I} - {\rm I}g} \right)s$$

$$\therefore$$ $${10^{ - 3}} \times 100 = \left( {10 - {{10}^{ - 3}}} \right) \times S$$

$$\therefore$$ $$S \approx 0.01\,\,\Omega $$

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