Question

1. In the circuit below the switch is set to connect the resistor to the capacitor. After a very long time the switch is moved to connect the capacitor the inductor. Which of the following is false? a. After the switch is moved to its final position, the energy stored in the capacitor plus the energy stored in the inductor will always be CV2/2 b. After the switch is moved to its final position, the charge on the capacitor and the current in the inductor will vary in time according to sine or cosine functions. c. The maximum current through the inductor will be V(C/L) d. The energy stored in the capacitor will always be larger than the energy stored in the inductor. R An electromagnetic wave traveling in the -x direction in vacuum has a frequency 2X1014HZ. The electric field in the wave has maximum value of 2 V/m. If we define the time and position such that the electric field has maximum value at position x-0 at time 0, a possible equation describing the electric field is: 2. a. E (2 V/m) sin [ (4.2 x 10 /m)x - (1.3 x105 Hz)t]i b. E-(2 V/m) cos [ (4.2 x 106 /m)x + (1.3 x1015 Hz)t] k c. E=(1 V/m) sin [ (1.3 x 1015 /m)x - (4.2 x10 Hz)t] k d. E (4 V/m) cos [ (4.2 x 106 /m)x + (1.3 x1015 Hz)t]

Answer 1

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