## Refractive Index Of Different Liquids Using Hollow Prism

Published on Apr 02, 2024

### Abstract

A prism is a transparent optical element with flat, polished surfaces that refract light. Prisms can be made from any material that is transparent including glass, plastic and fluorite.

A prism can be used to break light up into its constituent spectral colors. Prisms can also be used to reflect light, or to split light into components with different polarizations.

### Objective

To find refractive index of different liquids using hollow prism.

### Theory

#### Refraction:

The refractive index of the liquid is given by the formula:

Where:

μ = refractive index of the liquid

δm = the angle of minimum deviation

r = angle of refraction

i = angle of incidence

A = angle of prism

### Materials Required:

• Hollow glass prism

• Various liquids like water, carbon disulphide, benzaldehyde etc.

• Bell pins

• Drawing board

### Procedure:

• Fix a white sheet of paper on the drawing board with help of drawing pins.

• Keep the prism and mark the outline of it as ABC.

• Drop a normal PQ on the side AB.

• Draw the angle of incidence in accordance with the normal PQ and place 2 pins so that they appear to be in the straight line.

• Place the prism filled with given sample of liquid ,on the marked outline ABC.

• Now take the pins and place them on the side AC so that all the 4 pins appears to be in same line.

• Remove the prism and draw the line joining the points so obtained.

• Mark the diagram as shown in the figure.

• Repeat this with different liquids and different angle of incidence

### Results

Refractive indices at room temperature:

#### • Benzaldehyde

o Actual: 1.546

o Experimental: 1.504

#### • Water

o Actual: 1.33

o Experimental: 1.306

#### • Dil . Sulphuric acid

o Actual: 1.355

o Experimental: 1.351

### Precautions

• Angle of incidence should lie b/w 35-60 degree.

• Pins should be vertically fixed and should lie in same line.

• Distance b/w two points should not be less than 10mm.

• Same angle of prism should be used for all observation.

• Arrow head should be marked to represent emergent and incident ray.

• wikipedia.org