JEE Main · 2014 · 06 Apr 2014 · Offline · Units & Measurement

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The current voltage relation of diode is given by , where the applied voltage is in volts and the temperature T is in degree Kelvin. If a student makes an error measuring while measuring the current of 5 mA at 300 K, what will be the error in the value of current in mA?
  1. (A)0.5 mA
  2. (B)0.05 mA
  3. (C)0.2 mA✓ Correct
  4. (D)0.02 mA

Answer: (C)

Solution

Fix the operating point first: at mA and K, , so . The sensitivity of current to voltage is mA per volt. A voltage uncertainty of V therefore appears as a current uncertainty of mA.

JEE Main · 2014 · 06 Apr 2014 · Offline · Single correct option

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