[单选题]
Diamonds are highly valued because of the
df+ccxga(v:1cz ni*f. 1hq(oir sp
p)nqs*y+gvem 7 43o:bp)/cy x j;ujimarkle. This is caused by total internal reflection, which reflects most of the light that falls o
q/ x b:gy +p*s)jmoi; 3u7j)pcyn vm4ento a cut diamond out of the face we see. Fake gems, called 'paste', are often used in jewellery because they are cheaper. However, paste gems sparkle much less than real diamonds.
The diagrams show a possible path of light through a real diamond, and another through a fake.
If:
- $n=$ refractive index;
- $n_{d}$ is the refractive index of the diamond
- $n_{f}$ is the refractive index of the fake
- $v=$ speed of light
- $v_{d}$ is the speed of light in the diamond
- $v_{f}$ is the speed of light in the fake
Which row in the table contains only statements which must be true?
Post time 2024-1-26 22:03:40