Answer:
The velocity of the wave is 12.5 m/s
Explanation:
The given parameters are;
he frequency of the tuning fork, f = 250 Hz
The distance between successive crests of the wave formed, λ = 5 cm = 0.05 m
The velocity of a wave, v = f × λ
Where;
f = The frequency of the wave
λ = The wavelength of the wave - The distance between crests =
Substituting the known values gives;
v = 250 Hz × 0.05 m = 12.5 m/s
The velocity of the wave, v = 12.5 m/s.
The components that must be present for work to be considered is a force and a movement in the same direction as the force. In the basic definition of work, a magnitude and displacement that occurs in the same direction is what makes up work. Among the choices, the correct answer is the first one.
A) 
The magnitude of the capacitive reactance is given by

where
is the angular frequency
C is the capacitance
While the magnitude of the inductive capacitance is given by

where L is the inductance.
Since we want the two reactances to be equal, we have

So we find

B) 7449 rad/s
In this case, we have
is the inductance
is the capacitance
Therefore, substituting in the formula for the angular frequency, we find

C) 
Now we can us the formulas of the reactances written in part A). We have:
- Capacitive reactance:

- Inductive reactance:

We already know the formula for finding the energy of a photon with this wavelength as:
<span>E = ħc / λ
</span>The information's that we already know are:
h = Plancks constant
= <span>6.626x10^-34 Js
c = light speed
= </span><span> 2.999x10^8 m/s
</span><span>λ = Wavelength of the light as given in the question
</span> = <span>670.8x10^-9 m
E = amount of energy
Then
E = (</span>6.626x10^-34) * (2.999x10^8)/ (<span>670.8x10^-9)
= </span><span>2.962x10^-19 J</span>
Answer:
b. There is no definite top to the atmosphere. The pressure and density gradually get smaller as the altitude gets larger.
Explanation:
There is no specific top of the atmosphere. It varies from place to place. But generally it is considered to be 480 kilometers thick. But majority of its thickness is limited to 16 km only above earth surface. The pressure and density gradually get smaller as the altitude gets larger. The air pressure at sea level is 14.7 pounds per square inch and it decreases to 10 pounds per square inch at a height of 3 kilometers. From the above discussion we say that option B is correct