1. Real or Virtual? Real images A real image is one which can be produced on a screen and is formed by rays that converge. Imaginary images A virtual image cannot be formed on a screen and is produced by rays which only seem to come from the image.
5. Reflection off a plain mirror Image is: Virtual. Upright. The same size as object. Laterally inverted. Apparent distance from mirror to image is the same as the distance from the object to the mirror.
9. Reflection off a concave mirror Type of image formed depends on the distance of the object from the mirror.
10. Reflection off a concave mirror If object is between mirror and F image is: Virtual Upright Larger
11. Reflection off a concave mirror If object is further than F from the mirror image is: Real Inverted Laterally inverted As the distance is increased the image size decreases. http://www.phys.ufl.edu/~phy3054/light/mirror/applets/cavemir/Welcome.html
12. Drawing a ray diagram for a concave mirror Example 1 Draw a ray that travels parallel to the axis towards the mirror and reflects through the focal point in front of the mirror. 1 F F 2 Draw a ray that travels through the focal point in front of the mirror and reflects parallel to the axis.
13. Drawing a ray diagram for a concave mirror Example 2 1 F F Draw a ray that travels parallel to the axis towards the mirror and reflects through the focal point in front of the mirror. Draw a ray that reflects off the centre of the mirror at the same angle it was incident. 2
14. Drawing a ray diagram for a convex mirror Example 1 1 2 F F Draw a ray that travels towards the focal point behind the mirror and reflects parallel to the axis. Draw a ray that travels parallel to the axis towards the mirror and reflects in a direction that makes it look like it originated at the focal point behind the mirror.
15. Drawing a ray diagram for a convex mirror Example 2 1 2 F F Draw a ray that travels towards the focal point behind the mirror and reflects parallel to the axis. Draw a ray that travels parallel to the axis towards the mirror and reflects in a direction that makes it look like it originated at the focal point behind the mirror.
17. Light through a concave lens Light rays diverge. They appear to originate from a focal point in front of the lens. The image is: Virtual Upright
18. Light through a convex lens f = focal length F = focal point C = optical centre
19. Light through a convex lens Light rays converge to focal point behind lens. Type of image formed depends on the distance of the object from the lens. http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=48
20. Light through a convex lens If an object is further than 2F image is: Real Inverted Smaller
21. Light through a convex lens If an object is at 2F image is: Real Inverted Same size
22. Light through a convex lens If an object is between 2F and F image is: Real Inverted Larger
23. Light through a convex lens If an object is between F and C image is: Virtual Erect Larger
24. Drawing a ray diagram for a convex lens Draw: A ray straight through the centre of the lens. A ray that travels parallel to the axis towards the lens and refracts through the focal point behind the lens. A ray through the focal point in front of the lens that refracts parallel to the axis.
25. Drawing a ray diagram for a convex lens Example 1 2 1 F F 3
26. Drawing a ray diagram for a convex lens Example 2 2 F F 1
27. Drawing a ray diagram for a concave lens Draw: A ray straight through the centre of the lens. A ray that travels parallel to the axis which refracts as if it came from the focal point in front of the lens. A ray that travels towards the focal point behind the lens which refracts parallel to the axis.
28. Drawing a ray diagram for a concave lens Example 1 2 3 F F 1
29. Drawing a ray diagram for a concave lens Example 2 2 3 F F 1
