<h2>Answer: decibels
</h2>
The decibel
is the relation between two values: the pressure produced by a sound wave and a pressure taken as a reference. Resulting in a dimensionless value.
It should be noted that itself<u> is not a unit of measure</u>, since in reality the unit is bel
(which <u>is not part of the International System of Units</u>) in honor of Alexander Graham Bell.
However, given the amplitude of the measured elements in practice, its submultiple, the decibel, is used. That is, this quotient is a logarithmic expression, where
For an uniformly accelerated motion, we can write

where

is the acceleration of this motion, which in this problem is the gravitational acceleration, with a negative sign because it points downward, against the direction of the motion; h=0.540 m is the distance covered by the flea, and

is the initial velocity.
At the maximum height, the velocity is zero, so

. Therefore we can solve to find

:
Answer:
Cycles per second is dependent on the construction of the alternator and the 120 volts is dependent upon the current and resistance in the circuit according to the ohms law.
Explanation:
We are given with AC of 120 volts, 20 amperes and 60 hertz frequency.
<u>According to the Ohm's law, we find its resistance:</u>



So, this 6 ohm resistance controls the current controls the magnitude of the AC current, while the frequency of the current remains constant and depends upon the construction and rotational speed of the armature of the alternator producing the current.
Here the value of frequency is the number of times the current changes its direction or the polarity in one second.