Question

Use the figure at the right for problems 1 and 2. [6] 1. A 9.61 m2 resistor, 6.55 uH inductor and switch are connected in series across an ideal. EMF source E 9.50 V. How much energy is stored in the magnetic field of the inductor when switch S is closed and the magnetic field becomes stable? Answer: (a) 9.05 mJ. (b) 12.5 mJ (c) 19.6 mJ. R L ( (d) 24.3 mJ. (e) 29.4 mJ. [6] 2. In the previous problem, how long after switch S is closed until the magnetic field is stable? Answer: (a) 1.38 ms. (b) 1.85 ms. (c) 2.33 ms. (d) 2.79 ms. (e) 3.41 ms. (f) [8] 3. An AC generator is connected to a circuit. The generator's emf is Eft) 192 V sin(ast). If the maximum current that results is 150 mA circuit, a 5.01 x 107 rad/s and the phase angle is -77.6 degrees, complete the following sin (at [8] 4. The amplitude of an alternating current is Ima 12.2 x 10 Amperes. (e) 60.5 A What is value of Ims? (f) Answer: (a) 18.0 A. (c) 32.1 A (b) 25.0 A. (d) 47.5 A. [4] 5. In a series RLC circuit, the resistance is R= 42.8 m. At a certain frequency the circuit is in resonance and the value of the inductive reactance at that time is XL, is 57.5 mQ. At that time the capacitive reactance Xc must be Answer: (a) 0, (d) 42.8 m2, (b) 11.4 m2, (e) 57.5 m2, (c) 21.4 m2, (f) [10] 6. Which of the following is (are) TRUE? Circle it (them). (a) A transformer is a device that can be used to increase or decrease the amplitude of an alternating voltage. (b) A paramagnetic material is repelled by the poles of a magnet. (c) A current carrying solenoid is a good example of a magnetic dipole. (d) Magnetic field lines form closed loops. (e) A diamagnetic material is attracted to the poles of a magnet.

Answer 1

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