Physics – 3.1 General properties of waves | e-Consult

To demonstrate diffraction due to a gap using a ripple tank, the following apparatus is required: a ripple tank filled with water, a light source (e.g., a torch), a barrier with a narrow gap (e.g., a piece of cardboard with a small slit cut in it), and a screen placed at an angle to the ripple tank's surface.

The experimental procedure involves shining the light source onto the water surface of the ripple tank. The barrier with the gap should be placed in the path of the ripples. The screen should be positioned to receive the diffracted ripples.

Observations will show that the ripples passing through the gap will spread out after passing through the barrier. Instead of continuing in a straight line, the ripples will bend around the edges of the gap. This spreading out of the ripples is diffraction. The pattern on the screen will show areas of higher and lower intensity, demonstrating the constructive and destructive interference that occurs during diffraction.