Simple Lab Activity Report - Dispersion of Light

Dispersion of Light

Lab Activity:

Dispersion of Light through a Prism

Apparatus Required:

Prism, Torch Light, Screen (Thick Paper Sheet tor Cardboard Sheet),  Black Paper sheet, Table and wooden plank

Procedure:

• Take a Prism and place it on the table.  
• Take a black paper sheet and cut it into a size equal to the size of torch outer glass, and make a small hole in the middle of the paper sheet, such that a narrow light ray beam emerges from the torch light. 
• If black sheet is not available, we can also use a wooden plank with a small hole at the center point and arranged between the torch light and prism, such that a narrow light ray beam falls on the one side of the prism.  
• Now focus the torch towards the prism, the path of the thin beam of light falls on the one side of the prism with an acute angle.
• Arrange a cardboard sheet or thick paper sheet on the other side of the prism as a screen.
• Adjust the Prism and the screen until the different colours (VIBGYOR) appear on the screen.

Observation:

        When a light beam passes through the prism, it splits into seven colours (VIBGYOR).  Splitting of white light into seven colours is called 'Dispersion of Light'.

Precautions:

• Take care a narrow light beam to fall on the prism for good results. 
• After forming the colours on the screen, keep the prism undisturbed.
• Handle the Prism and Torch carefully.