Engineering Board Exam Reviewer · Ohm's Law · medium

A voltmeter reads 8.4 V across a resistor and an ammeter in series reads 42 mA. What is the resistance?

  1. 20,
  2. 200,
  3. 100,
  4. 400,

Answer

B. 200,

Solution

R=V/I=8.4/0.042=200, .

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