The energies E1 and E2 of the two radiations are 25eV and 50eV respectively. The relation between their wavelengths i.e. λ1 and λ2 will be . . . . . . . .

Answer: Option C

We are given two radiations with energies E₁ = 25 eV and E₂ = 50 eV, and we need to determine how their wavelengths λ₁ and λ₂ are related.
The energy of radiation is inversely proportional to its wavelength, as described by the equation:
E = h * c / λ
Where:
E is the energy of the radiation,
h is Planck's constant,
c is the speed of light, and
λ is the wavelength.
Since energy and wavelength are inversely proportional, we can express the ratio of the wavelengths in terms of the energies:
λ₁ / λ₂ = E₂ / E₁
Substituting the values for the energies:
λ₁ / λ₂ = 50 / 25 = 2
This means that the wavelength λ₁ is twice the wavelength λ₂. Hence, λ₁ = 2λ₂.
Thus, the correct answer is Option C.