Refer to FIGURE 2.1 below and answer the questions that follow - NSC Electrical Technology Digital - Question 2 - 2021 - Paper 1
Question 2
Refer to FIGURE 2.1 below and answer the questions that follow.
2.1.1 Identify the multivibrator in FIGURE 2.1.
2.1.2 State the polarity of the pulse provided on t... show full transcript
Worked Solution & Example Answer:Refer to FIGURE 2.1 below and answer the questions that follow - NSC Electrical Technology Digital - Question 2 - 2021 - Paper 1
Step 1
Identify the multivibrator in FIGURE 2.1.
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Answer
The multivibrator in FIGURE 2.1 is a monostable multivibrator, which is used to generate a single output pulse in response to an input trigger.
Step 2
State the polarity of the pulse provided on the inverting input when switch S1 is pressed.
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Answer
When switch S1 is pressed, the polarity of the pulse on the inverting input is negative, as it is being pulled down towards the ground potential.
Step 3
State TWO functions of the 741 op-amp in the circuit.
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Answer
The 741 op-amp functions as a comparator, comparing the input voltage at the inverting terminal with the threshold voltage.
It is used to amplify the output signal, converting a small voltage change at the inputs into a larger voltage change at the output.
Step 4
In which mode will the circuit be in when S1 is pressed.
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Answer
The circuit will be in the triggered mode when switch S1 is pressed, creating a temporary change in the output state.
Step 5
State the polarity of the voltage present on pin 3 after switch S1 is pressed.
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Answer
After switch S1 is pressed, the polarity of the voltage present on pin 3 will be positive as the op-amp output switches to high state.
