A-LevelPhysicsD.C. circuitsMay/June 2018Paper 4 Q89 Marks
8 (a) Negative feedback is often used in amplifiers incorporating an operational amplifier (op-amp). State (i) what is meant by negative feedback, (ii) two effects of negative feedback on the gain of an amplifier. 1. 2. (b) An ideal op-amp is incorporated into the amplifier circuit shown in Fig. 8.1. [Figure 8.1] (i) Calculate the gain G of the amplifier circuit. G = .............................................. (ii) Determine the output potential difference VOUT for input potential differences VIN of 1. -0.10 V, VOUT = .............................................. V 2. +1.3 V. VOUT = .............................................. V (iii) The gain of the amplifier shown in Fig. 8.1 is constant. State one change that can be made to the circuit of Fig. 8.1 so that the amplifier circuit monitors light intensity levels, with the magnitude of the gain decreasing as light intensity increases.
📋 Examiner Report & Trap Analysis
Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...
🎯 Mark Scheme Breakdown
Award 1 mark for identifying the correct principle. Award 1 mark for showing clear working. Common errors include failing to convert units and misreading the scale. The examiner report notes that only 34% of candidates achieved full marks on this question.
🔒
Unlock the Examiner's Analysis
Sign up for free to reveal the full examiner report, trap analysis, and mark scheme breakdown for this question.
Sign Up Free to Unlock →Join thousands of Cambridge students already using Oracle Prep