Page 203 - text book form physics kssm 2020

Chapter 5
Waves
Drawing Diagram of Refraction of Plane Water Waves
Figure 5.37(a) shows plane wavefronts in deep water region approaching shallow water region.
Figure 5.37(b) which shows wavefronts of refracted waves can be drawn using four steps.
Incident wave A Normal
1 2

Deep region B

Shallow region
4

3

C

Figure 5.37(a) Figure 5.37(b)

Th e steps to draw refraction of plane water waves are as follows:

Step 1:
Draw an arrowed line AB perpendicular to the incident
wavefront to represent direction of propagation of the
incident wave.

Step 2:
Draw the normal which is perpendicular to the boundary of
the deep region and shallow region at B.

If water wave propagates from
shallow region to deep region,
Step 3:
Draw an arrowed line BC, which is nearer the normal direction of propagation of
than AB to represent the direction of propagation of the the refracted wave is bent
refracted wave. away from the normal.

Step 4:
Draw three lines perpendicular to BC to represent the
refracted wavefronts. Th e lines have to be closer to one
another compared to the incident wavefronts.

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3.2.2
5.4.2
5.4.2