Consider the voltage phasor in Figure 32.4, shown at three instants of time. (i) Choose the part of the figure, (a), (b), or (c), that represents the instant of time at which the instantaneous value of the voltage has the largest magnitude. (ii) Choose the part of the figure that represents the instant of time at which the instantaneous value of the voltage has the smallest magnitude.
(i)
Answer to Problem 33.1QQ
Explanation of Solution
A phasor diagram is arrow whose length represents the amplitude of an AC voltage or current. The phasor diagram rotates counterclockwise about the origin with angular frequency of the AC quantity. The maximum rotation of the length of the arrow with angular frequency represents the largest magnitude of voltage. Hence, the Figure (c) represents the largest magnitude of voltage at instant of time
Conclusion:
Therefore, the Figure (c) represents the largest magnitude of voltage at instant of time because of maximum rotation of arrow in counterclockwise with maximum frequency.
(ii)
Answer to Problem 33.1QQ
Explanation of Solution
A phasor diagram is arrow whose length represents the amplitude of an AC voltage or current. The phasor diagram rotates counterclockwise about the origin with angular frequency of the AC quantity. The minimum rotation of the length of the arrow with minimum angular frequency represents the minimum voltage. Hence, the Figure(b) represents the minimum voltage at instant of time because of minimum rotation of the length of the arrow with minimum angular frequency represents.
Thus, the Figure (b) represents the smallest magnitude of voltage at instant of time.
Conclusion:
Therefore, the Figure (b) represents the smallest magnitude of voltage at instant of time because of minimum rotation of arrow in counterclockwise with minimum frequency.
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Chapter 33 Solutions
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