Question

Wave number of radiation having wavelength 5000 angstrom

Answer 1

Answer:

$2 \times {10}^{6}$

Explanation:

$wave \: no. = \frac{1}{wavelength} \\ = \frac{1}{5000 \times {10}^{ - 10} } \\ = 2 \times {10}^{6}$

Answer 2

Answer:

Given:

Wavelength (λ) = 5000 Å

To Find:

Wave Number (v)

Solution:

We know that,

$\sf Wave\;Number = \dfrac{1}{Wavelength}$

Mathematically,

$\red{\boxed{\boxed{\sf v = \dfrac{1}{\lambda} }}}$

We are asked to find Wave Number (v)

Given that,

λ = 5000 Å

Therefore,

Substituting the above value in the given formula  

We get,

$\implies \sf v = \dfrac{1}{\lambda}$

$\implies \sf v = \dfrac{1}{5000 \times 10^-10}$

Since, Å = 10⁻¹⁰ m

$\implies \sf v = \dfrac{1}{5 \times 10^-7}$

$\implies \sf v = \dfrac{10^7}{5}\;m^-1$

$\implies \sf v = \dfrac{1}{5} \times 10^7\;m^-1$

$\implies \sf v = 0.2 \times 10^7\;m^-1$

$\sf \implies v = 2 \times 10^6\;m^-1$

Or

$\implies \sf v = 2000000\;m^-1$

Hence

Wave number of radiation having wavelength 5000 angstrom is 2000000 m⁻¹

Or

2 x 10⁶ m⁻¹