1. A longitudinal wave is a wave wherein the motion of the particle is parallel to the direction of the wave, while transverse wave is a wave where the motion of the particle is perpendicular to the direction of the wave.

2. Law of Reflection

3. Example: Law of Reflection

4. Refraction is the change in the direction of a wave due to the change in its speed/velocity

5. Example: Refraction of light wave

6. Refraction of sound wave

7. Refraction of water waves

8. Refraction of sound waves

9. Diffraction is the bending of a light wave as it passes through a narrow opening, forming semicircular light waves. It occurs when water waves passes through an obstacle.

10. Example of diffraction Water waves

12. Diffraction of light

13. Diffraction of light on a silver surface

14. Diffraction of white light through a diffraction grating

15. Diffraction of light forms a rainbow pattern

16. INTERFERENCE Is simply the combination of waves passing the same medium at the same time. Constructive interference happens when two waves of the same frequency, in phase, and traveling in the same direction meet. Destructive interference results when two out-of-phase waves interfere or are in opposite directions and the combined amplitude is zero.

17. Interference of water waves

19. Interference of water waves

20. The constructive and destructive interference of light waves

21. CONVEX MIRROR

22. CONCAVE

23. Concave mirror

24. Convex and concave

25. Concave mirror

26. Difference between concave and convex mirrors Principal Axis -The principal axis is an imaginary line that cuts through the center of a mirror dividing it symmetrically in half. Imagine this as a curve on a piece of paper. Focal Point -The focal point is a spot on the principal axis where light would intersect if it were to strike the mirror parallel to the principal axis.

27. Shape -Concave mirrors curve inward, creating a focal point in front of the mirror. Convex mirrors curve outward creating a focal point behind the mirror. Concave Image -Because of their shape and focal point placement, images in concave mirrors appear upside down and far away. However, when you move closer, the object enlarges. If you get close enough, the object enlarges more and the image is right-side up. Convex Image -In a convex mirror, images appear right-side up, shrunken and virtual, or placed somewhere behind the mirror.

28. Bend -Concave mirrors bend inward, while the curvature of a convex mirror is outward. Concave Images -Concave mirrors reflect images upside down when viewed from afar. They also cause images to become larger when viewed from close up. Convex Images -Images reflected on convex mirrors appear smaller than they really are--which can be seen in the majority of automobiles. As opposed to concave mirrors, they offer a smaller and wider view.

29. USES OF THE CONCAVE MIRROR 1. to make a microscope 2. used in headlights of vehicles to send parallel rays to infinity 3. shaving mirror to get an enlarged image of the face 4. used by dentist’s to see a bigger image of the tooth/teeth

30. 5. used in solar powered projects where they reflect the heat rays of the sun so that they are concentrated at one place. 6. magnifying mirror 7. make-up mirror 8. telescopes

31. USES OF CONVEX MIRROR 1. view finder in vehicles because it reflects a wider image area. 2. used in supermarkets and stores for surveillance 3. making sunglasses lenses and telescopes. Lenses helps reflect some of the sunlight some of the sunlight away from the eyes. 4. magnifying glass 5. used as home decor

32. Structure of the human eye

33. Converging lens and Diverging lens

34. Basic Types of lenses 1. the convex lens (orconverging lens) 2. the concave lens (or diverging lens). Due to refraction, light rays bend as they pass into and out of the lens Convex lenses are shaped so that the rays converge together; concave lenses are shaped to spread rays apart.

35. Eye lens anatomy