When two waves with different frequencies combine, two new waves are created, with frequencies at the sum and difference of the two original ones. The new ones are called the 'beats'.
Original two frequencies: 267.8 Hz, 266.4 Hz .
Beat at the sum = (267.8 + 266.4) = 534.2 Hz .
Beat at the difference = (267.8 - 266.4) = 1.4 Hz .
In this situation, we're typically not aware of the sum-beat at 534 Hz.
Our consciousness is flooded with the two original frequencies, and
with hearing the whole combined sound going "wah wah wah" at
1.4 times per second. But the 534-Hz note is there too ... part of
what makes the whole thing sound so ragged and discordant.
Answer:
1. The precession of the equinoxes.
2. Changes in the tilt angle of Earth’s rotational axis relative to the plane of Earth’s orbit around the Sun.
3. Variations in the eccentricity
Explanation:
These variations listed above; the precession of the equinoxes (refers, changes in the timing of the seasons of summer and winter), this occurs on a roughly about 26,000-year interval; changes in the tilt angle of Earth’s rotational axis relative to the plane of Earth’s orbit around the Sun, this occurs roughly in a 41,000-year interval; and changes in the eccentricity (that is a departure from a perfect circle) of Earth’s orbit around the Sun, occurring on a roughly 100,000-year timescale. which influences the mean annual solar radiation at the top of Earth’s atmosphere.
As soon as I see "Which...", I know that the last part of the question is the list of answer choices, but you decided not to let us see them.
The answer is: A 33-Newton force pointing upward.
Answer: 2.83 minutes
Explanation:
It is understood that trains are approaching. That is, they have speeds of equal magnitude but opposite. When train A travels x meters northbound, then train B travels the same distance southbound.
Therefore trains approach at a speed of:

Then:

Where x is the distance between the trains

So the time in which both trains meet is:

This is:

<em />
<em>How long will it be before they reach one another ?</em>
<h3>2.83 minutes</h3>