Question

Question: Which of the following has the higher frequency:(a) light having a wavelength of 10²or 10⁴ nm;

(b) light having a wavelength of 100 nm or 100 µm;

(c) red light or blue light?

Short answer

Answer

(a) Light having a wavelength of ${10}^2$nm.

(b) Light having a wavelength of 100 nm.

(c) Blue light

Step-by-step solution

Electromagnetic radiation

Radiations having dual properties of both particles and waves are called electromagnetic radiations.

Particles of radiation having a discrete amount of energy are called photons.

Due to the wave nature of these photons, they can be characterized by their wavelength and frequency.

Wave nature of electromagnetic radiation

The wave nature of radiation is defined using its wavelength and frequency.

Wavelength is the distance from the peak of one wave to the peak of an adjacent wave of radiation.

Frequency is the number of waves passing through a point in unit time.

Comparing frequency of radiations

Frequency and wavelength are inversely proportional. Therefore, radiation having a lower wavelength will have a higher frequency.

(a) Light having a wavelength of ${10}^2$ nm will have a higher frequency than light with a frequency of ${10}^4$nm.

(b) Light having a wavelength of 100 nm will have a higher frequency than light with a frequency of 100$\mathrm{\mu m}$ .

(c) The wavelength of blue light is less than the wavelength of red light. Therefore, the blue light will have a higher frequency.