Правка разделов «Statement», «Solution», «Answer»

jzmicer правка от
правка #18587 предыдущая #18586 ← раньше
@@ -1,11 +1,22 @@
### Statement
−$12.2.2.$ [Insert the problem statement]
+$12.2.2$. How do the wavelength and wave speed change when a wave transitions into a medium with refractive index $n$? Does the frequency of the wave change?
### Solution
+It is known that the refractive index determines the change in the speed of light in a medium compared to a vacuum. Therefore, by definition
+$$
+c' = \frac{c}{n}
+$$
+We also know that the energy of a photon is given by $E = h\nu$; this energy does not change when transitioning into another medium, so the frequency $\nu$ also does not change.
−$12.2.2$. How do the wavelength and wave speed change when a wave transitions into a medium with refractive index $n$? Does the frequency of the wave change?
+The wavelength is then defined as:
+$$
+\lambda = \frac{c'}{\nu} = \frac{\lambda}{n}
+$$
+
#### Answer
−[Insert a concise answer or boxed result]
+$$
+\boxed{c'=\frac{c}{n};\quad \lambda=\frac{\lambda}{n};\quad \nu=const}
+$$