Given below are two statements: one is labelled as Assertion (A)...

The propagation speed of an electromagnetic wave is given by $v = \dfrac{E_0}{B_0} = \dfrac{1}{\sqrt{\mu\varepsilon}}$.
The ratio of electric field amplitude to magnetic intensity amplitude (wave impedance) is given by $\dfrac{E_0}{H_0} = \sqrt{\dfrac{\mu}{\varepsilon}}$.

For a non-magnetic dielectric medium, the relative permeability $\mu_r = 1$ (so $\mu = \mu_0$) and the relative permittivity $\varepsilon_r > 1$ (so $\varepsilon > \varepsilon_0$).

Substituting these values, the speed becomes $v = \dfrac{1}{\sqrt{\mu_0 \varepsilon_0 \varepsilon_r}}$, which is less than the speed in vacuum ($c = \dfrac{1}{\sqrt{\mu_0 \varepsilon_0}}$). Thus, the propagation speed decreases.

Similarly, the ratio $\dfrac{E_0}{H_0}$ becomes $\sqrt{\dfrac{\mu_0}{\varepsilon_0 \varepsilon_r}}$, which is less than the vacuum value ($\sqrt{\dfrac{\mu_0}{\varepsilon_0}}$). Thus, the ratio of electric field to magnetic intensity also decreases.

Therefore, the Assertion is incorrect because it states that the ratio $E_0/H_0$ increases. The Reason is correct as it accurately states that both quantities become smaller than their vacuum values.

Answer: (A) is not correct but (R) is correct