Refraction

OP39 show the refraction of light as it passes from: air to glass, air to water, glass to air, water to air; show refraction of light through a lens; demonstrate the operation of a magnifying glass

Refraction is the apparent bending of light that occurs when light enters a transparent medium from another transparent medium.

To determine the refractive index of a transparent material

Draw the outline of the block on the page.

Line up 2 pins as so they make a line to the block, which makes an angle to the block.

Look through the block

place a pin so it blocks out the image of the 2 pins through the glass block

place another pin in so it blocks the line of the 3 pins when looking through the glass block

Draw lines that join the dot to the glass block

then under the block join the two points, where the drawn lines meet the outline of the block, to each other.

refractive index = Sin i/Sin r = n

A good summary of the applications of refraction

optical fiber ....

prisms

any lens ...

OP39 show refraction of light through a lens; demonstrate the operation of a magnifying glass

http://www.physics.uiowa.edu/~

USES OF REFRACTION

Make a glass beaker disappear !!!

http://www.thenakedscientists.com/HTML/content/kitchenscience/exp/making-pyrex-invisible/

The Microscope

The microscope, which consists of two converging lenses, was invented by Zacharius Janssen about 1590.

In the microscope the first lens is called the objective lens and the object to be viewed is placed just outside its focus, to form a magnified inverted real image. This real image is the object for the second lens, called the eyepiece lens, and is placed just inside the focus of the eyepiece lens. The final image formed is magnified, virtual, still inverted and formed far away from the eyepiece lens so that the it can be viewed with a relaxed eye.

umallik/adventure/geo-optics/lightnw.htm