Physics Circle home Student Login

Home›Chapters›Current Electricity PYQs›Kirchhoff's Laws & Measuring Instruments›Question 148

MHT CET 2020 (16 Oct, Shift 1) · Kirchhoff's Laws & Measuring Instruments

Kirchhoff's Laws & Measuring Instruments question from MHT CET 2020 (16 Oct, Shift 1)

Q148MHT CET 2020 · 16 OCT · SHIFT 1Medium

Kirchhoff's Laws & Measuring Instruments

An ammeter of resistance 20 Ω20\ \Omega gives full scale deflection, when 1 mA1\text{ mA} current flows through it. What is the maximum current that can be measured by connecting 4 resistors each of 16 Ω16\ \Omega in parallel with the ammeter?

Show answer and solution

Answer: (a)

  1. Four 16 Ω16\ \Omega in parallel: S=4 ΩS = 4\ \Omega.
  2. I=Ig(1+GS)=1 mA×(1+204)I = I_g\left(1 + \dfrac{G}{S}\right) = 1\text{ mA} \times \left(1 + \dfrac{20}{4}\right)
  3. I=6 mAI = 6\text{ mA}. So the answer is (a).
Report a mistake

More questions on Kirchhoff's Laws & Measuring Instruments