The output voltage of an AC generator is given by $\Delta v = ( 170 \mathrm { V } ) \sin ( 60 \pi t )$. The generator is connected across a $20.0 - \Omega$ resistor. By inspection, what are the current when t = 0.005 0 s.

What is the advantage of transmitting power at high voltages?

Two loudspeakers are placed above and below one another and are driven by the same source at a frequency of $500 \mathrm{~Hz}$. (a) What minimum distance should the top speaker be moved back in order to create destructive interference between the speakers?

The AM band extends from approximately 500 kHz to 1 600 kHz. If a 2.0-$\mu \mathrm { H }$ inductor is used in a tuning circuit for a radio, what are the extremes that a capacitor must reach to cover the complete band of frequencies?

The phase angle of an RLC series circuit with an inductive reactance of 200 Ω and a capacitive reactance of 100 Ω is 40.0 degrees. What is the value of the resistor in this circuit?

You push down on a raft floating on a lake. The raft sinks and then vibrates up and down for a short time. How does the period of its vibrations depend on the size and mass of the raft?

What is the resistance of a lightbulb that uses an average power of 75.0 W when connected to a 60.0-Hz power source having a maximum voltage of 170 V?

A bat flying at 5.00 m/s is chasing an insect flying in the same direction. If the bat emits a 40.0-kHz chirp and receives back an echo at 40.4 kHz, (a) what is the speed of the insect? (b) Will the bat be able to catch the insect? Explain.

A water bottle in the shape of a cylinder has a volume of 500 cubic centimeters. The diameter of a base is 7.5 centimeters. What is the height of the bottle? Justify your answer.

An AC source operating at 60 Hz with a maximum voltage of 170 V is connected in series with a resistor (R = 1.2 $k \Omega$) and an inductor (L = 2.8 H). When the current is zero, what are the magnitudes of the potential difference across the resistor, the inductor, and the AC source?

A commuter train passes a passenger platform at a constant speed of 40.0 m/s. The train horn is sounded at its characteristic frequency of 320 Hz. What overall change in frequency is detected by a person on the platform as the train moves from approaching to receding?

An AC source operating at 60 Hz with a maximum voltage of 170 V is connected in series with a resistor (R = 1.2 $k \Omega$) and an inductor (L = 2.8 H). When the current is at a maximum, what are the magnitudes of the potential differences across the resistor, the inductor, and the AC source?

A series RLC circuit has a resistance of $22.0 \Omega$ and an impedance of $80.0 \Omega$. If the rms voltage applied to the circuit is 160 V, what average power is delivered to the circuit?