2.99 See Answer

Question: The switch S in Figure 20.27

The switch S in Figure 20.27 is closed at t = 0 and the current at a reference time tref > 0 is Iref. If the circuit is changed as described below and the switch is again closed at t = 0, determine whether the current I at the same time tref would be greater than, less than, or equal to the original value of Iref. Indicate your answers with G, L, or E, respectively. (a) Both the battery voltage ε and the resistance R are doubled. (b) The inductance L is doubled. (c) The battery voltage ε, the resistance R, and the inductance L are each doubled. Figure 20.27:
The switch S in Figure 20.27 is closed at t = 0 and the current at a reference time tref > 0 is Iref. If the circuit is changed as described below and the switch is again closed at t = 0, determine whether the current I at the same time tref would be greater than, less than, or equal to the original value of Iref. Indicate your answers with G, L, or E, respectively.
(a) Both the battery voltage ε and the resistance R are doubled.
(b) The inductance L is doubled.
(c) The battery voltage ε, the resistance R, and the inductance L are each doubled.

Figure 20.27:


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> Suppose XL > XC in Figure 21.12. If switch A is closed, what happens to the phase angle? (a) It increases. (b) It decreases. (c) It doesn’t change. Figure 21.12:

> If switch A is closed in Figure 21.12, what happens to the impedance of the circuit? (a) It increases. (b) It decreases. (c) It doesn’t change. Figure 21.12:

> For the circuit in Figure 21.8, is the instantaneous voltage of the source equal to (a) The sum of the maximum voltages across the elements, (b) The sum of the instantaneous voltages across the elements, or (c) The sum of the rms voltages across the elem

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> Which of the following statements are true about light waves? (a) The higher the frequency, the longer the wavelength. (b) The lower the frequency, the longer the wavelength. (c) Higher - frequency light travels faster than lower - frequency light. (d) T

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> Figure P20.3 shows three edge views of a square loop with sides of length â„“ = 0.250 m in a magnetic field of magnitude 2.00 T. Calculate the magnetic flux through the loop oriented (a) Perpendicular to the magnetic field, (b) 60.0&Acirc

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> A bar magnet is positioned near a coil of wire, as shown in Figure P20.15. What is the direction of the current in the resistor when the magnet is moved (a) To the left and (b) To the right? Figure P20.15:

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> In Figure P20.14, what is the direction of the current induced in the resistor at the instant the switch is closed? Figure P20.14:

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2.99

See Answer