Question

The angular frequencies, for three em waves E₁ , E₂ , E₃ have values , ω₁, ω₂ and ω₃ , respectively. If ω₁ is greater than both ω₂ and ω₃ and ω₂ is less than ω₃ , the three em waves could be, respectively,

(1) x – rays, visible light, microwaves

(2) γ – rays, uv – rays, microwaves

(3) visible light, infrared rays, radio waves

(4) uv – rays, radio waves, visible light

Answer 1

(4) uv – rays, radio waves, visible light

We are given that ω₁ > (ω₂ or ω₃) or and ω₂ < ω₃

∴ The angular frequencies are in the order ω₁ > ω₃ > ω₂

The three em waves must, therefore, have their frequencies as per this requirement. In all the options given, ω₁ is greater than both ω₂ and ω₃ . However, in the first three options, ω₂ < ω₃ . It is only in the fourth option that we have ω₂ < ω₃ .