Question

What resistance must be connected in parallel to the galvanometer to turn it into an ammeter capable of reading electric currents up to a 10.01 A ?

• A. $0.1\Omega$
• B. $1\Omega$
• C. $10\Omega$
• D. none of these

Answer 1

The correct option is A $0.1\Omega$

The maximum possible current permissible in galvanometer is $10mA=0.01A$, so the maximum voltage across galvanometer is $100\times 0.01=1V$.

The maximum current through $R$ is $10.01-0.01=10A$. As $V_R=1V$, the resistance $R=1/10=0.1\Omega$