Answer:
C. The decrease in speed as the wave approaches shore.
Explanation:
The waves break when approaching the shore because the depth decreases. Thus, the wave travels more slowly and increases its height. There comes a time when the part of the wave on the surface travels faster than the one that travels under water, the ridge destabilizes and falls against the ground.
Answer:

Explanation:
Refractive Index: It is a measure to find how fast the light travels through a medium. It is ration of the speed of light in vacuum to speed of light in the medium. Speed of light is not constant and varies depending on the density of the medium.
In vacuum the speed of light is 300000 km/s and is denoted by c. When the light beam enters any medium the speed will decrease. Here it is given that the speed in plastic is v. Thus the refractive index(n) is given as:

It is a dimensionless no.
Answer:
The magnitude of the external electric field at P will reduce to 2.26 x 10⁶ N/C, but the direction is still to the right.
Explanation:
From coulomb's law, F = Eq
Thus,
F = E₁q₁
F = E₂q₂
Then
E₂q₂ = E₁q₁

where;
E₂ is the external electric field due to second test charge = ?
E₁ is the external electric field due to first test charge = 4 x 10⁶ N/C
q₁ is the first test charge = 13 mC
q₂ is the second test charge = 23 mC
Substitute in these values in the equation above and calculate E₂.

The magnitude of the external electric field at P will reduce to 2.26 x 10⁶ N/C when 13 mC test charge is replaced with another test charge of 23 mC.
However, the direction of the external field is still to the right.
The average current is 0.10 A.
<h3>Current </h3>
Charge moving through a location on a circuit at a constant rate is called current. When numerous coulombs of charge pass over a wire's cross section in a circuit, it produces a large current. It is not necessary for a wire to be moving at a fast speed in order to have a high current if the charge carriers are tightly packed into the wire. To put it another way, many charge carriers traveling through the cross section is sufficient; they do not need to travel a great distance in a single instant. The amount of charges that flow through a cross section of wire on a circuit, as opposed to how far they travel in a second, is what determines current.
A charge of 12 c passes through an electroplating apparatus in 2. 0 min. what is the average current?
Learn more about current here:
brainly.com/question/2264542
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