The figure shows an LR circuit with a switch and a 240-volt battery. At the instant the switch is closed the current in the circuit and the potential difference between points a and b, Vab, are
a.
0 A, 0 V
b.
0 A, 240 V
c.
0 A, +240 V
d.
0.024 A, 0 V
e.
0.024 A, +240 V
[Ques. 2] There is no current in the circuit shown in the figure below until the switch is closed. The current through the 20- resistor the instant after the switch is closed is either 1 15 A or 2 5.0 A, and the current through the 20- resistor after the switch has been closed a long time is either 3 5.0 A or 4 15 A. Which combination of the above choices is correct?
a.
1 and 3
b.
1 and 4
c.
2 and 3
d.
2 and 4
e.
None of these
[Ques. 3] The switch in the figure is closed at t = 0 when the current I is zero. When I = 15 mA, what is the potential difference across the inductor?
a.
240 V
b.
60 V
c.
0
d.
180 V
e.
190 V
[Ques. 4] Before the switch is closed in the figure, the potential across the capacitor is 200 V. At some instant after the switch is closed, the instantaneous current is 0.70 A. What is the energy in the capacitor at this instant?
a.
49 mJ
b.
31 mJ
c.
80 mJ
d.
0.13 J
e.
62 mJ
[Ques. 5] For the circuit shown, what is the rate of change of the current in the inductor when the current in the battery is 0.50 A?
a.
600 A/s
b.
400 A/s
c.
200 A/s
d.
800 A/s
e.
500 A/s
[Ques. 6] Kevlar forms from the monomers shown. Show the structure of the polymer, in the usual bracket format.
[Ques. 7] Polypropylene forms from the monomer CH
3CH=CH
2. Show the structure of the polymer, in the usual bracket format.
[Ques. 8] Complete the equation:
[Ques. 9] Complete the equation:
[Ques. 10] Draw the structural formula for 1-chloro-2-methylpentane.
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