Answer:
Sound is produced when an object vibrates, creating a pressure wave.
Explanation:
This pressure wave causes particles in the surrounding medium (air, water, or solid) to have vibrational motion. ... The human ear detects sound waves when vibrating air particles vibrate small parts within the ear.
Answer:
b) the refracted ray has an angle of 90 degrees
Explanation:
The angle of incidence is measured with respect to the normal separation of the media. The critical angle for total internal reflection occurs is:

Here
and
are the refractive index of the mediums. This equation is an application of Snell's law, for the case where the refracted ray has an angle of
.
Answer: wavelength !!
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Answer:
The answer to your question is vo = 5.43 m/s
Explanation:
Data
distance = d= 5.8 m
height = 3 m
height 2 = 1.7 m
angle = 60°
vo = ?
g = 9.81 m/s²
Formula
hmax = vo²sinФ/ 2g
Solve for vo²
vo² = 2ghmax / sinФ
Substitution
vo² = 2(9.81)(3 - 1.7) / 0.866
Simplification
vo² = 19.62(1.3) / 0.866
vo² = 25.51 / 0.866
vo² = 29.45
Result
vo = 5.43 m/s