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Question
If the resistance R1 is increased (Figure), how will the readings of the ammeter and voltmeter change?
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Solution
Let us redraw the circuit diagram to find the change in reading of the ammeter and voltmeter.
So, `I_BR_1 + V_(BE) = V_(BB)`
Base current, `I_B = (V_(BB) - V_(BE))/R_1`
`I_B ∝ 1/R_1`
So, R1 is increased, IB is decreased.
Now, the current in the ammeter is collector current IC.
IC = βIB as IB is decreased, IC is also decreased and the reading of the voltmeter and ammeter also decreased.
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