Physics 236 Worksheet: Chapter 33, AC Circuits

1.     Whenever the frequency in an AC series circuit increases, the ____ will also increase.

a.     current

b.      inductive reactance

c.      capacitive reactance

d.     impedance

2.     Which of the following is not true about a circuit operating at its resonant frequency?

a.     The inductive and capacitive reactances are equal.

b.      The phase angle is zero.

c.      The current is at a maximum.

d.     The power is at a maximum.

e.     The impedance is at a maximum.

3.     In a circuit the resistance is 400 W, the inductive reactance is 900 W, and the capacitive reactance is 600 W. The impedance is

a.     1900 W

b.      700 W

c.      500 W

d.     100 W

4.     In a capacitor

a.     the voltage leads the current by 90°

b.      the current leads the voltage by 90°

c.      the voltage and current are 180° out of phase

d.     the voltage and current are in phase

5.     The width of the power vs frequency curve (Dw) of a series RLC circuit is narrow for circuits with

a.     high current.

b.      low current

c.      high resistance.

d.     low resistance.

6.     A transformer that has more turns on the secondary than on the primary will

a.     step up voltage and current.

b.      step down voltage and current.

c.      step up voltage and step down current.

d.     step down voltage and step up current.

7.     Identify the circuit type represented by each of the impedance vs. frequency graphs.

a.     Circuit with inductance and resistance only. (RL circuit)  _________

b.      Circuit with capacitance and resistance only. (RC circuit)  _________

c.      Circuit with capacitance, inductance, and resistance. (RLC circuit)  _________

 

 

Ans: 1-b, 2-e, 3-c, 4-b, 5-d, 6-c, 7a) Fig. 2, 7b) Fig. 1, 7c) Fig. 3