Chapter 32: AC Circuits

A $110Hz$source of emf has a peak voltage of $50V$. Draw the emf phasor at $t=3.0ms$.

A series RLC circuit consists of a $50\Omega$ resistor, a localid="1650177582139" $3.3mH$ inductor, and a localid="1650177586647" $480nF$ capacitor. It is connected to an oscillator with a peak voltage of localid="1650177591401" $5.0V$. Determine the impedance, the peak current, and the phase angle at frequencies :

(a) localid="1650177630395" $3000Hz$(b) localid="1650177635339" $4000Hz$and (c) localid="1650177638990" $5000Hz.$

At what frequency f do a $1.0\mu F$capacitor and a $1.0\mu H$inductor have the same reactance? What is the value of the reactance at this frequency?

For the circuit of FIGURE EX32.32,

a. What is the resonance frequency, in both rad/s and Hz?

b .Find $V_R$and $V_L$at resonance.

c. How can $V_L$be larger than ${\epsilon }_o$? Explain.

For the circuit of figure $Ex32.33$,

a. What is the resonance frequency, in both $rad/s$ and $Hz$?

b. Find $V_r$and$V_c$at resonance.

c. How can$V_c$be larger than${\epsilon }_0$? Explain .

The heating element of a hair drier dissipates $1500W$when connected to a $120V/60Hz$power line. What is its resistance?

A resistor dissipates $2.0W$when the rms voltage of the emf is$10.0V$. At what $rms$voltage will the resistor dissipate $10.0W$$?$

For what absolute value of the phase angle does a source deliver $75\%$of the maximum possible power to an RLC circuit?

The motor of an electric drill draws a $3.5A$rms current at the power-line voltage of $120V$rms. What is the motor's power if the current lags the voltage by$20°$.

A series RLC circuit attached to a $120V/60Hz$power line draws a $2.4A$rms current with a power factor of $0.87$. What is the value of the resistor?