Answer:
7. 1.56
8. A curved line that slopes upward
Explanation:
7. The curve for quartz at the left side of the graph (400 nm) is just above the middle of the distance between 1.5 and 1.6, so is best approximated by 1.56.
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8. The graph shows n vs. wavelength. The question asks about n vs. frequency. Frequency is inversely proportional to wavelengh, which means you need to describe the curve from right to left, rather than left to right. From right to left, the curve rises, so can be called "a curved line that slopes upward."
<h2>Explanation:</h2><h3>3. </h3>
When light bounces back, it is <em>reflected</em>. (That's why you see your <em>reflection</em> in a mirror.) When light is bent from the path it is taking, it is <em>refracted</em>. The only answer choice that makes correct use of these terms is the third choice:
- Part of the ray is <em>refracted</em> into ray B; part of the ray is <em>reflected</em> as ray R.
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<h3>4.</h3>
The index of refraction is the ratio of the sine of the angle of incidence to the sine of the angle of refraction. Both angles are measured from the normal to the surface. The angle of refraction here is 12.5° less than the angle of incidence, 44°, so is 31.5°. Then the index of refraction of the medium is ...
n = sin(44°)/sin(31.5°) = 0.69466/0.52250 = 1.3299 ≈ 1.33
- none of the offered choices is correct. The closest is 1.34.
Answer:
e) A changing magnetic field produces an electric field.
Explanation:
Ok, we start with a magnetic field and let's study how it affects the motion of a single electron. As the magnetic field changes, it will cause an electromotive force, that moves the electron, and because now we have a moving electron, now we will have an electric field. (Such that the direction of the electromotive force opposes the direction in which the magnetic field changes). This also can be deduced if we look at the third Maxwell's equation:
dE/dx = -dB/dt
This says that the spatial change in an electric field depends on how the magnetic field changes as time pass.
Then the correct option is e) A changing magnetic field produces an electric field.
Answer:
107 m
Explanation:
Convert km/h to m/s:
128.4 km/h × (1000 m / km) × (1 h / 3600 s) = 35.67 m/s
Distance = rate × time
d = 35.67 m/s × 3.0 s
d = 107 m
