# The Electromagnetic Spectrum Visible Light

PhysicsElectromagnetic waves

#### Class 11th Physics - Elasticity

6 Lectures 1 hours

#### Class 11th Physics - Oscillations

12 Lectures 2 hours

#### Class 11th Physics - Waves

14 Lectures 3 hours

## Introduction

In accordance with the discoveries of physics, all the aspects that have electromagnetic radiation are generally known by the name of light. However, the human eye can detect only a small section of this electromagnetic spectrum. The human eye consists of cone-shaped cells those are responsible for making this electromagnetic spectrum visible to the eye. Based on such conceptualisation of physics, the present tutorial will include an explanation of the visible light spectrum.

### What is the visible spectrum of light?

Figure 1: Visible light spectrum

The visible part of the electromagnetic spectrum to a human eye is referred to as the visible spectrum. Light is generally defined as the electromagnetic radiation that is mostly detected by the human eye or visible to an eye.

It has been seen observed that the human eye is found to be sensitive differently to the spectrums of different wavelengths. As per the information, the range of wavelength that is recognised by the human eye is from 380 to 700 nanometers (Nasa, 2022).

This particular spectrum of visible light does not contain all the colours as all colours are not been distinguishable for the human eye. For an instance, the presence of magenta is missing in the spectrum as it is beyond the detection power of the human eye.

### Wavelength and colour spectrum chart

The terms of physics such as frequency and energy shares a close relationship with the wavelength of the electromagnetic spectrum. This phenomenon is considered the responsible attribute for the determination of the colour of the radiation. On the scale of the electromagnetic spectrum, the boundaries present between two colours are not visibly and clearly separated rather the colours are drastically blended with each other (Fan et al. 2019).

This is the reason that the colour band of the visible light spectrum, the ultraviolet region is identified at one edge whereas infrared radiations are identified to be placed at another edge of the band. In the visible light spectrum, each wavelength is represented by a particular colour. Each of these colours consists of different characteristics and wavelengths are distinct.

### Colour and Temperature

According to the laws of physics, the more temperature the object will detect, the shorter will the wavelength be. This is the basic reason that a human eye can observe the change of colour of the white light after passing through a prism. For example, the flame of a blow torch can be seen to be shifted from reddish to bluish one in accordance with the colour based on the adjustment of temperature (Researchgate, 2022). This is the reason that helps the scientist mark the temperature of the stars as the stars with the hotter atmosphere will determine different wavelengths of light in comparison to the cooler ones.

### The electromagnetic spectrum of visible light

Figure 2: Electromagnetic spectrum of light

One of the most common aspects of the electromagnetic spectrum of light is that the electromagnetic waves has the ability to travel through the spec or vacuum. The main reason for this phenomenon is that the electromagnetic waves can transport energy through the vacuum of outer space. The production of electromagnetic waves is possibly done by the vibration of magnetic or vibrating charges (Researchgate, 2022).

Therefore, the electromagnetic spectrum contains a wide range of frequencies and wavelengths. In order to study, the entire visible spectrum is generally broken down into small specific parts. This segregation can be done based on observation where it has been seen in which manner; the electromagnetic waves interact with matter in which manner.

### Visible light astronomy

Figure 3: Visible light astronomy

In accordance with the electromagnetic spectrum reflected by the stars far away is the main medium of measuring the temperature of the particular star. For instance, it can be stated that the temperature of the surface level of the sun is 5,800 Kelvin (Nasa, 2022). This is the reason that the peak wavelength of the sunlight is about 550 nm. It will turn to be reddish if the temperature of the sum were cooler in comparison to the present measured temperature. On the other hand, if the sun were hotter, it will appear in blue colour.

## Conclusion

The current tutorial has shed light on defining the concept of the visual spectrum which usually refers to the specific wavelength of the electromagnetic spectrum that is possibly detected by the human eye. The tutorial has further included the discussion based on the wavelength and the colour spectrum chart of white light which can be only seen when the light passes through a prism. It has been seen that every single spectrum of light is of a different wavelength. Based on this wavelength the spectrum defines their place in the seven-coloured chart developed by the refraction and dispersion of light.

### FAQs

Q1. How much of the electromagnetic spectrum is made up of visible light?

The light that possibly travels to our eyes constitutes less than 1% of the visible spectrum. In accordance with the scientist, the measurement represents 0.0035% of the total magnetic spectrum as the human eye is considered to be limited in its range.

Q2. What is defined by the phrase: electromagnetic spectrum?

White light generally consists of seven different lights of different wavelengths. Following this concert, the electromagnetic spectrum is defined as the entire distribution of electronic radiations in accordance with wavelength or the frequency

Q3. What is visible light?

In accordance with the discoveries of physics, $\mathrm{400\:THz\:to\:800\:THz\:}$ is considered the frequency level of visible light. Light with different frequency that is not more than $\mathrm{400\:nm\:to\:700\:nm\:}$ can be distinguished by the optical of the human eye. This is the main reason that makes the light visible optically.

Q4. Which wavelength of electromagnetic energy is visible to the human eye?

The perceivable section of the electromagnetic spectrum by the human eye is recognised as the visible spectrum. The range of wavelength that can be detected by the human eye is referred to as the range from 330 to 700 nanometres.

Updated on 13-Oct-2022 11:19:47