Answer
As the angle of incidence increases in Figure 2.8, a point is finally reached where the refracted ray does not emerge at the second layer but lie along the interface. This particular angle of incidence at which the angle of refraction is 90° and the refracted ray lies along the interface is known as the critical angle. At and beyond the critical angle, there is no transmitted ray and therefore a very high reflected ray will be recorded .
Therefore,
sinθisin90=Vp1Vp2
But, sin 90 = 1.
At critical angle,
sinθcritical=Vp1Vp2
A critical refracted wave travels along the interface between layers and is refracted back into the upper layer at the critical angle. The waves refracted back into the upper layer are called head waves or first-break refractions because at certain distances from a source, they are the first arriving energy. Recorded first-break refraction is shown in Figure 2.10.
Note that these first-break refractions can give us important information about the shallow velocities on land seismic data.
Note also that seismic data are acquired in such a way that reflections from horizons of interest are in the pre-critical region, even at the farthest offset in the data.
In reality, part of the seismic energy arriving at an interface is transmitted and refracted, and another part of the energy is reflected at that same interface. Given that there are many reflectors in the subsurface, there will be many paths from source to receiver, each of them with a different travel time. The proportion of energy reflected depends on the material properties of the two bounding layers and on the angle of incidence
During a car crash, the car decelerates extremely rapidly, so inertia causes you to move forward quickly. If there wasn't an airbag to slow you down, you might fly out the windshield.
The air bag increases impulse by increasing the time during which a force acts on you (impulse=force*time). This decreases your forward momentum, so you'll have a better chance of surviving.
The turn ratio of the transformer is 40.
<h3 />
<h3>What is a transformer?</h3>
A transformer is an electrical device that is used to step up or step down voltage.
The formula for calculating the turns ratio of a transformer is given below.
<h3> Formula</h3>
- a = V/v.......... Equation 1
Where:
- V = Primary voltage
- v = Secondary voltage
- a = Turns ratio of the transformer
From the question,
Given:
Substitute the values above into equation 1
Hence, The turn ratio of the transformer is 40.
Learn more about transformers here: brainly.com/question/6450076
planetary accretion is the term that is used
