Answer:
4.6 kHz
Explanation:
The formula for the Doppler effect allows us to find the frequency of the reflected wave:

where
f is the original frequency of the sound
v is the speed of sound
vs is the speed of the wave source
In this problem, we have
f = 41.2 kHz
v = 330 m/s
vs = 33.0 m/s
Therefore, if we substitute in the equation we find the frequency of the reflected wave:

And the frequency of the beats is equal to the difference between the frequency of the reflected wave and the original frequency:

When light passes from one medium to another, part of it continues on
into the new medium, while the rest of it bounces away from the boundary,
back into the first medium.
The part of the light that continues on into the new medium is <em>transmitted</em>
light. Its forward progress at any point in its journey is <em>transmission</em>.
Its direction usually changes as it crosses the boundary. The bending is <em>
refraction</em>.
The part of the light that bounces away from the boundary and heads back
into the first medium is <em>reflected</em> light. The process of bouncing is <em>reflection</em>.
Answer:
Explanation:
mg = kx
x = mg/k
x = 30(80)(9.8)/2.8e7 = 0.00084 m ≈ 1 mm
You need to know everything is made of atoms they are always colliding and they are never still because you'd think that every thing in space is still all the time even if it's not making visibly
"Gravity force" (also known as "weight")