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As the drawing illustrates, a siren can be made by blowing a jet of air through 20 equally spaced holes in a rotating disk. The time it take
Question
As the drawing illustrates, a siren can be made by blowing a jet of air through 20 equally spaced holes in a rotating disk. The time it takes for successive holes to move past the air jet is the period of the sound. The siren is to produce a 2087.8-Hz tone. What must be the angular speed ω (in rad/s) of the disk?
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Physics
5 years
2021-08-18T20:46:22+00:00
2021-08-18T20:46:22+00:00 2 Answers
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Answer: 656 rad/s
Explanation:
Angular frequency is also called radial circular frequency. It measures angular displacement per unit time. It’s unit is rad/s. It is also greater than the regular frequency by a factor of 2π. Hence, angular frequency, ω = 2πf
If 1 revolution(20 hole) = 20 cycle per revolution.
Then, 2087.8(cycle) = x revolution
X revolution = 2087.8/20)
X revolution = 104.39 revolution
ω = 2πf
ω = 2 * π * 104.39
ω = 655.98676
ω ~ 656 rad/s
Answer:
Explanation:
Given:
n = 20 holes
f = 2087.8 Hz
1rev = 20 hole
= 20 cycle/rev
ω = (2π × f) × n
n = number of cycles per revolution
= 1/20
= 0.05 rev/cycle
ω = 2π × 2087.8 × 0.05
= 655.9 rad/s