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Calculate, in SI units, the wave number of the lines of frequencies 4×10^14Hz and 5×10^16Hz.

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Final answer:

The wave number can be calculated using the formula k = 2π / λ, where λ is the wavelength. By finding the wavelength using v = fλ, we can determine the wave number. For the given frequencies of 4×10^14 Hz and 5×10^16 Hz, the wave numbers are approximately 8.38×10^6 m^-1 and 1.05×10^9 m^-1, respectively.

Step-by-step explanation:

The wave number (k) of a wave can be calculated using the formula:

k = 2π / λ

where λ is the wavelength of the wave. To find the wave number, we first need to determine the wavelength using the formula:

v = fλ

where v is the velocity of the wave and f is the frequency. Using the given frequencies of 4×10^14 Hz and 5×10^16 Hz, we can calculate the wavelengths, and then use those values to find the wave numbers.

For the frequency of 4×10^14 Hz:

  • Velocity of light (v) = 3×10^8 m/s
  • Frequency (f) = 4×10^14 Hz
  • Wavelength (λ) = v / f = (3×10^8 m/s) / (4×10^14 Hz) = 7.5×10^-7 m

Using the obtained wavelength, we can now calculate the wave number:

  • Wave number (k) = 2π / λ = (2π) / (7.5×10^-7 m) ≈ 8.38×10^6 m^-1

Similarly, for the frequency of 5×10^16 Hz:

  • Frequency (f) = 5×10^16 Hz
  • Wavelength (λ) = v / f = (3×10^8 m/s) / (5×10^16 Hz) = 6×10^-9 m

Wave number (k) = 2π / λ = (2π) / (6×10^-9 m) ≈ 1.05×10^9 m^-1

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