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Question 10
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(a)
) Draw a labeled block diagram of a closed-loop control system showing
the direction of signal flow.
(b) State three domestic appliances that use the closed-loop control
system. |
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T
The expected answers were: |
(a) Labelled block diagram of control system |
e |
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Comparator |
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I Controller |
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I |
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Feedback |
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Feedback |
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signal |
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network |
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(b) (i) Refrigerator
(ii) Pressing iron
(iii) Air conditioner
(iv) Any other |
The question was on Control Circuits. The question was unpopular. The
performance of the very few candidates that attempted it was reportedly
poor. |
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