A galvanmeter has a coil of resistance $200 \Omega$ with a full scale deflection at $20 \mu \mathrm{A}$. The value of resistance to be added to use it as an ammeter of range $(0-20) \mathrm{mA}$ is:
  • A$0.40 \Omega$
  • B$0.20 \Omega$
  • C$0.50 \Omega$
  • D$0.10 \Omega$
JEE MAIN 2024, Diffcult
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