Operational Amplifiers (Op‑Amps) — A/L Physics

How do I practise Operational Amplifiers (Op‑Amps)?

1 question with a worked solution

1. In an ideal operational amplifier connected in an inverting amplifier configuration, the input resistor is R_in = 10 kΩ and the feedback resistor is R_f = 100 kΩ. What is the closed-loop voltage gain (A_v) of the amplifier?
   1. A) +10
   2. B) -10
   3. C) -0.1
   4. D) +11
   Check my answer

   Correct answer: B) -10

   For an ideal inverting operational amplifier, the inverting terminal is held at virtual ground (0 V). The closed-loop voltage gain is given by A_v = V_out / V_in = - R_f / R_in = - 100 kΩ / 10 kΩ = -10 (the negative sign indicates a 180° phase inversion).

   Show worked solution

   Step 1: Formula for inverting op-amp gain: A_v = - R_f / R_in. Step 2: A_v = - 100 kΩ / 10 kΩ = -10. Answer: -10.
   Modelled on: the A/L Physics examination pattern

Get this auto-marked

Next in the syllabus

Where does Operational Amplifiers (Op‑Amps) fit in the syllabus?

Unit 9.6 · Year 2 · Term 2