A sinusoidal forcing function is described by Vm cos(ωt). The forced response in a series RL circuit is found to be I(t) = A cos(ωt - θ). What is the expression for the amplitude A?

Correct answer: Vm / sqrt(R^2 + (ωL)^2)

Explanation

This question tests the formula for the magnitude of the current response in a series RL circuit, which is derived from the magnitude of the circuit's total impedance.

Other questions

Question 1

In the context of sinusoidal steady-state analysis, what is the term for the abbreviated complex representation of a real sinusoidal current or voltage, which contains only amplitude and phase information?

Question 2

What is the correct phasor representation V for the time-domain voltage v(t) = 100 cos(400t - 30 degrees) volts?

Question 3

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Question 4

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Question 5

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Question 7

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Question 8

In the frequency domain, what is the definition of impedance (Z)?

Question 9

What is the correct relationship between admittance (Y), conductance (G), and susceptance (B)?

Question 10

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Question 11

What is the equivalent impedance of the parallel combination of a 5 mH inductor and a 100 microFarad capacitor at an operating frequency of omega = 10,000 rad/s?

Question 12

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Question 13

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Question 14

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Question 15

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Question 16

Find the Thévenin equivalent impedance Zth seen by the -j10 ohm impedance in the circuit described in Example 10.11.

Question 17

In a phasor diagram for a series RLC circuit, if the current phasor I is used as the reference (along the positive real axis), how would the voltage phasor for the inductor, VL, be oriented?

Question 18

The primary advantage of using the complex forcing function method to solve for the sinusoidal steady-state response is that it transforms the circuit's governing equation from what to what?

Question 19

What is the inductive reactance of a 30 mH inductor at a frequency of 1000 rad/s?

Question 20

What is the impedance of a 2 pF capacitor at an operating frequency of ω = 3000 rad/s?

Question 21

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Question 22

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Question 23

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Question 24

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Question 25

In the frequency-domain circuit of Figure 10.21, with a source of 100/0 degrees V, a resistor -j5 ohms, a resistor 5 ohms, and an inductor j5 ohms, what is the phasor current I1?

Question 26

What is the equivalent impedance Zeq for the circuit in Example 10.7, which has a 1.5 kOhm resistor in series with the parallel combination of a 1 kOhm resistor and an inductor with impedance j1 kOhm, and a capacitor with impedance -j2 kOhm?

Question 27

A circuit has a source vs(t) = 40 sin(3000t) V. What is the correct phasor representation Vs to use for frequency-domain analysis?

Question 28

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Question 29

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Question 30

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Question 31

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Question 32

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Question 33

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Question 34

The term 'steady-state response' in the context of sinusoidal sources refers to what condition?

Question 35

A circuit contains two sinusoidal sources: one at 3 cos(5t) A and another at 2 cos(3t) A. To find the power dissipated by a 10 ohm resistor in the circuit, what is the correct procedure?

Question 36

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Question 37

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Question 38

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Question 39

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Question 40

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Question 42

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Question 43

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Question 44

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Question 45

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Question 46

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Question 47

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Question 48

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Question 49

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Question 50

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