A beat is an interference pattern between two sounds of slightly different frequencies, perceived as a periodic variation in volume whose rate is the difference of the two frequencies. Frequency beat is equal to,
The reference frequency in our case would be 392Hz, and since there is the possibility of the upper and lower range for the amount of beats per second that the two possible frequencies are heard would be
Therefore the two possible frequencies the piano wire is vibrating at, would be 396Hz and 388Hz
Answer:
an electromagnetic wave with a wavelength in the range 0.001–0.3 m, shorter than that of a normal radio wave but longer than those of infrared radiation. Microwaves are used in radar, in communications, and for heating in microwave ovens and in various industrial processes.
Answer:
Recessed incandescent luminaires not marked type ic and those marked for installing directly in insulated ceilings must not have insulation over the top of the luminaire.
Explanation:
Depending on how they interact with insulation, lighting fixtures are rated at various levels. Non-IC rated lighting fixtures can accommodate higher wattage bulbs, but they also pose the greatest fire risk when used with the incorrect insulation.
In locations with insulation, light fixtures that are not IC rated may be installed. But there is a condition. The distance between the fixture and any insulation should be 3 inches. But the 3 inch gap in the insulation would negate the goal of insulation by producing a lot of uninsulated space, so this defies logic. Building a box-style cover to cover the fixture on the attic side is one option to fix this. Drywall or foil-faced foam insulation can be used to create this box. After the cover is put in place, insulation can be added for maximum effectiveness.
To learn more about recessed incandescent luminaries. Click brainly.com/question/17218799
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Draw a circuit that contains 2 batteries, three lights in parallel and a switch that controls the whole circuit.
Answer: 0.25 m/s
Explanation: Speed = wavelengt · frequency
v = λf and frequency is 1/period f = 1/T
Then v = λ/T = 5 m / 20 s = 0.25 m/s
