Answer:
The frequency of a wave is 35 Hz.
Explanation:
Speed of a wave is 140 m/s
Wavelength of a wave is 4 m
It is required to find the frequency. The relation between frequency, speed and the wavelength of a wave is given by :

f is frequency

So, the frequency of a wave is 35 Hz.
Answer:
<em>The car will be moving at 5.48 m/s at the bottom of the hill</em>
Explanation:
<u>Principle of Conservation of Mechanical Energy</u>
In the absence of friction, the total mechanical energy is conserved. That means that
is constant, being U the potential energy and K the kinetic energy
U=mgh

When the car is at the top of the hill, its speed is 0, but its height h should be enough to produce the needed speed v down the hill.
The Kinetic energy is then, zero. When the car gets enough speed we assume it is achieved at ground level, so the potential energy runs out to zero but the Kinetic is at max. So the initial potential energy is transformed into kinetic energy.
We are given the initial potential energy U=45 J. It all is transformed to kinetic energy at the bottom of the hill, thus:

Multiplying by 2:

Dividing by m:

Taking square roots:



v = 5.48 m/s
The car will be moving at 5.48 m/s at the bottom of the hill
Answer:
The epithelial cell shape and stratification are related to its function. For example, the skin is specialized to act as a "physical" barrier to the outside world. This barrier is both structural (multi-layered) and chemical in nature. Another example is the cells that make up the tubular elements of the kidney.
Explanation: