Question

The resistance of ammeter is $13R$ and its scale is graduated for a current upto $100\text{A}$ . After an additional shunt has been connected to this ammeter it becomes possible to measure current upto $750\text{A}$ shunt resistance is

• A. $2k\Omega$
• B. $20\Omega$
• C. $2\Omega$
  
• D. $0.2\Omega$
  

Answer 1

The correct option is C $2\Omega$


For given setup circuit diagram can be drawn as
Now,
$V_{AB}=V_{CD}$
$\Rightarrow 100\times 13=650\times R$
$R=2\Omega$.