Two piano strings are supposed to be vibrating at 132 Hz, but a piano tuner hears three beats every 2.0 s when they are played together. If one is vibrating at 132 Hz, what must be the frequency of the other (is there only one answer)?

A meteorite traveling 8500 m/s strikes the ocean. Determine the shock wave angle it produces in the air just before entering the ocean. Assume $T=20^{\circ} \mathrm{C}$.

A compact car with a mass of 875 kg, moving south at 15 m/s, is struck by a full-sized car with a mass of 1584 kg, moving east at 12 m/s. The two cars stick together, and momentum is conserved. a. Sketch the situation, assigning coordinate axes and identifying “before” and “after.” b. Find the direction and speed of the wreck immediately after the collision, remembering that momentum is a vector quantity. c. The wreck skids along the ground and comes to a stop. The coefficient of kinetic friction while the wreck is skidding is 0.55. Assume that the acceleration is constant. How far does the wreck skid after impact?

A meteorite traveling 8500 m/s strikes the ocean. Determine the shock wave angle it produces in the water just after entering. Assume $T=20^{\circ} \mathrm{C}$.

A 12.0-m-long conveyor belt, inclined at $30.0^{\circ}$, is used to transport bundles of newspapers from the mail room up to the cargo bay to be loaded onto delivery trucks. Each newspaper has a mass of 1.0 kg, and there are 25 newspapers per bundle. Determine the power that the conveyor develops if it delivers 15 bundles per minute.

A constant net force of 410 N is applied upward to a stone that weighs 32 N. The upward force is applied through a distance of 2.0 m, and the stone is then released. To what height, from the point of release, will the stone rise?

A bat emits short pulses of sound at a frequency of $1.60 \times 10^{5} \mathrm{Hz}$.As the bat swoops toward a flat wall at speed 30 m/s, this sound is reflected from the wall back to the bat. (a) What is the frequency of sound incident on the wall? (b) Consider the wall as a sound source at the frequency calculated in part (a). What frequency of sound does the bat hear coming from the wall?

A bird stands on a de electric transmission line carrying 2800 A. The line has $2.5 \times 10^{-5} \mathrm{\Omega}$ resistance per meter, and the bird's feet are 4.0 cm apart. What is the potential difference between the bird's feet?

The current in an electromagnet connected to a 240-V line is 17.5 A. At what rate must cooling water pass over the coils if the water temperature is to rise by no more than $7.50 \mathrm{C}^{\circ} ?$

As a bat flies toward a wall at a speed of $6.0 \mathrm{~m} / \mathrm{s}$, the bat emits an ultrasonic sound wave with frequency $30.0 \mathrm{kHz}$. What frequency does the bat hear in the reflected wave?

Two sound waves combine to create a wave with greater amplitude than either of them individually. What is this an example of?
A. damping
B. destructive interference
C. wave-boundary interaction
D. constructive interference

A battery with an emf of 12.0 V shows a terminal voltage of 11.8 V when operating in a circuit with two lightbulbs rated at 3.0 W (at 12.0 V) which are connected in parallel. What is the battery's internal resistance?

Two loudspeakers are 1.80 m apart. A person stands 3.00 m from one speaker and 3.50 m from the other. Calculate two other frequencies that also result in destructive interference at this point (give the next two highest). Let $T=20^{\circ} \mathrm{C}$.

A bat flies toward a wall at a speed of 5.0 m/s. As it flies, the bat emits an ultrasonic sound wave with frequency 30.0 kHz. What frequency does the bat hear in the reflected wave?