To find the angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of deviation. | Physics Practical Class 12 | Gaurav Kumar

 To find the angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of deviation.

Aim: -

To find the angle of minimum deviation for a given prism by plotting a graph between angle of incidence and angle of deviation.

APPARATUS: -

Glass prism, pins (drawing and office) drawing board, sharp pencil, protractor, meter scale.

THEORY: -

                            Angle of deviation = (i - e) - A

OBSERVATION: -

1.    Type of prism     =    equilateral glass prism.

2.    Angle of prism    60'    

3.    Table for variation of angle of deviation with angle of incidence.

Table

Graph: -

Do yourself

CALCULATION: -

At the lowest point M of the i - deviation curve, draw a tangent parallel to the X - axis such that tangent meets the Y - axis at point D. Read the angle of minimum deviation corresponding to the lowest point M of the graph.

RESLUT: -

The angle of minimum deviation, = ................... degree

PRECAUTIONS: -

1.    The position of the prism should not be disturbed on the white paper sheet.

2.    There should be no parallax between the image pins p3, p4, and object pins p1, p2.

3.    The minimum distance between two pins should be 10 cm.

4.    The first pin P1 should be fixed vey close to the prism.

5.    All the pins should be fixed perpendicular to the white sheep paper.