Geometric Optics

 

- Total Internal Reflection (6A44.10) link to picture 6a44_10.htm

-90 degree deviation (Modern Periscopes)

-180 degree deviation (Prism Binoculars)

-Reversing Prism

-Critical Angle (rotate disk until T.I.R. occurs, then draw in normal)

 

- Refractive Index (6A40.30)

-Show how a glass tube seems to disappear when immursed in a liquid of the same index of refraction as the glass

-pyrex and vegetable oil work well.

-For best effect, put your thumb over the end of the tube first. Then release when you want the tube to "disappear".

 

- Thin Lenses (6A60.20) link to picture 6a60_20.htm

-Two parallel lasers can be aimed toward a converging of a diverging lens.

-Turn on the lasers and use chalk dust to make the beams visible.

-The focal lengths are marked on the lenses.

 

- Rainbow (6A46.11)

-Place a clear plastic cup filled with water on the overhead projector.

-A circular rainbow will be visible on the ceiling.

 

- Reflection From Flat Surfaces (6A10.31) link to picture 6a10_31.htm

-The light entering a corner cube reflector is always reflected back parallel to its line of entry.

-If students are permitted to look in the mirror, they will always be able to see themselves, upside down.

 

- Reflection From Curved Surfaces (6A20.15)

-Two parallel lasers can be aimed toward a converging or a diverging mirror.

-Turn on the lasers and use chalk dust to make the beams visible.

-The focal lengths are about 12".

 

- Reflection From Flat Surfaces (6A10.10) link to picture 6a10_10.htm

-When using blackboard optics, put a few drops of glycerin on the suction cups, before fixing to the board.

-The Law of Reflection :<a=<b where <a denotes the incoming angle of the light ray (incoming angle made with the normal of the surface) and <b denotes the reflected angle of the light ray (reflected angle made with the normal of the surface).

 

- Straight Line Propagation of Light (6A02.15)

-Make shadow puppets on the wall.

 

- Reflection From Curved Surfaces (6A20.10) link to picture 6a20_10.htm

-Concave Mirrors give real images

-Convex Mirrors give virtual images

 

- Thin Lenses (6A60.10)

-Plano-Convex Lens has its focal length on the opposite side of where the object is placed relative to the lens.

-Plano-Concave Lens has its focal length on the same side of where the object is placed relative to the lens.

 

- Refraction at Flat Surfaces (6A42.10) link to picture 6a42_10.htm

-Simple Refraction:

-Less dense --> More Dense

-More dense --> Less Dense

-Parallel Displacement

- v=(dsin(a-b))/(sinb)

 

- Thick Lens (6A65.11)

-We have a wide selection of lenses, ranging in size, and power.