Diamonds are highly valued because of their sparkle. This is ca
3jzzn;m chp6kqfwa, dw 03oh*y15ri9used by total internal reflection, which reflects most of the light that falls onto a cut diamond out of the face we see. Fake gems, called 'paste', are often used in jewellery because they are cheaper. However, paste gem
dhckq19rf350w,3n mh* 6j oayz;z piw s 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?
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