Exams › NEET › Chemistry

The value of Planck’s constant is 6.63 × 10⁻³⁴ Js. The velocity of light is 3.0 × 10⁸ m s⁻¹. Which value is closest to the wavelength in nanometers of a quantum of light with frequency of 8 × 10¹⁵ s⁻¹?

1. 3 × 10⁷
2. 2 × 10⁵
3. 5 × 10⁸
4. 4 × 10¹

Correct answer: 4 × 10¹

Solution

The wavelength (λ) is calculated using the formula λ = c / ν, where c is the speed of light and ν is the frequency. Substituting c = 3.0 × 10⁸ m/s and ν = 8 × 10¹⁵ s⁻¹, we get λ = (3.0 × 10⁸) / (8 × 10¹⁵) = 3.75 × 10⁻⁸ m = 37.5 nm, which is closest to 4 × 10¹ nm.

Related NEET Chemistry questions

• Protons and neutrons are also called
• From the \( \alpha \) -particle scattering experiment, Rutherford concluded that: This question has multiple correct options
• Which of following was not explained by Rutherford?
• The energy of an electron in the ground state of \( \boldsymbol{H} \) atom is \( -\mathbf{1 3 . 6 e V} \) The negative sign indicates that:
• Outer electronic configuration of Cl⁻ is:
• The sub-shell with lowest value of (n + l) is filled up first. When two or more sub-shells have the same (n + l) value, the sub-shell with lowest value of 'n' is filled up first. Therefore, the correct order is:

⚔️ Practice NEET Chemistry free + battle 1v1 →