<u>Difference between pulse and periodic waves:</u>
A pulse wave is a sudden disturbance in which only one wave or a few waves are generated, such as in the example of the pebble. Thunder and explosions also create pulse waves. A periodic wave repeats the same oscillation for several cycles, such as in the case of the wave pool, and is associated with simple harmonic motion. Each particle in the medium experiences simple harmonic motion in periodic waves by moving back and forth periodically through the same positions.
<u>Difference between longitudinal and transverse waves:</u>
A transverse wave propagates when the disturbance is perpendicular to the propagation direction. An example of a transverse wave is where a woman moves a toy spring up and down, generating waves that propagate away from herself in the horizontal direction while disturbing the toy spring in the vertical direction.
In a longitudinal wave, the disturbance is parallel to the propagation direction. Example of longitudinal wave is where the woman now makes a disturbance in the horizontal direction—which is the same direction as the wave propagation—by stretching and then compressing the toy spring.
Answer:
What?-
Explanation:
Where’s the story or whatever like that?
Answer:
The resultant electric force is 14.8N to the right.
Explanation:
Since the three charges aren't in the same line, we have to break down the force in components. First, we need to know the distance from the third charge to the other ones. That is made using the Pythagorean Theorem. As the figure is symmetric with respect to the x-axis, the two distances are the same:

Now, we use the Coulomb's Law to obtain the magnitude of the individual forces caused by each charge on the third charge:

For the same reason the distances are the same, the magnitude of the forces are the same:

So, to get the resultant force, we have to break down this forces in components. To do this, we need their angles with respect to the x-axis. Let θ₁ and θ₂ be these angles, respectively. Then, we calculate them using trigonometry:

Now, we calculate the components of the forces:

Evidently, the y-components cancel out, and the resultant electric force on the third charge is
along the x-axis (to the right, because it's positive).
Complete Question
A spherical wave with a wavelength of 2.0 mm is emitted from the origin. At one instant of time, the phase at r_1 = 4.0 mm is π rad. At that instant, what is the phase at r_2 = 3.5 mm ? Express your answer to two significant figures and include the appropriate units.
Answer:
The phase at the second point is 
Explanation:
From the question we are told that
The wavelength of the spherical wave is 
The first radius is 
The phase at that instant is 
The second radius is 
Generally the phase difference is mathematically represented as

this can also be expressed as

So we have that

substituting values



Answer:
High altitude
Explanation:
Infrared rays are absorbed by water vapor in the lower parts of our atmosphere such as near the sea level.Infrared telescopes positioned on high mountains can observe the cosmos at a wavelength near-infrared. In this case, this telescope is positioned on a mountain top where the altitude is high.