Practice question · Numerical answer
Rutile titanium dioxide has a refractive index of about 2.70 and chalk about 1.57. Linseed oil is 1.48. By what factor is the rutile's difference from the oil greater than the chalk's?
Hints
- Work out each difference from 1.48 first.
- Divide 1.22 by 0.09.
Show the answer
13.6 (answers within ±0.5 count)
Why
By a factor of about 13.6. The differences are 1.22 and 0.09, and since scattering rises with that difference, this single ratio explains why titanium white obliterates whatever is under it while chalk disappears into an oil film and does nothing but occupy volume.
Practise Aqueous Media
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