Optics lab

Grade 10 ScienceOptics Unit

Station 2 - One Way Mirror Shoe Box

Once at this station make sure the following is in place:

Materials:

•(1) Reflect Views •(2) Object & Image Sticks•(1) White work surface

This is a picture of a public toilet in Switzerland that's made entirely out of one-way glass. No one can see you in there, but when you are inside, it looks like you're sitting in a clear glass box. http://www.snopes.com/photos/arts/toilet.asp

See-Through-Loo

Outside View

Inside View

7) What does this have to do with Refraction?

See-Through-Loo

Outside View

Inside View

Whenever light passes from one medium to another it partially refracts and partially reflects.

7) What does this have to do with Refraction?

Whenever light passes from one medium to another it partially refracts and partially reflects.

See-Through-Loo

Outside View

Inside View

7) What does this have to do with Refraction?

Whenever light passes from one medium to another it partially refracts and partially reflects.

See-Through-Loo

Outside View

Inside View

Did you notice the reflected ray in the activity?

Partial reflection / refraction alsooccurs in windows.

Part of the light striking the window refract through and part reflects back into the room

Inside the “Loo” is dark so that there is little light to refract out. Note the weak reflection from inside.

Outside the “Loo” is bright so there is lots of light to reflect back and refract inside.

See-Through-Loo

Outside View

Inside View

If there is a difference between light brightness on either side of a window, the light from the bright side will refract strongly through and reflect more strongly back into the room.

The person in the room will see a strong reflection of themselves compared to the image refracted from the other side

If there is a difference between light brightness on either side of a window, the light from the bright side will refract strongly through and reflect more strongly back into the room.

The person in the room will see a strong reflection of themselves compared to the image refracted from the other side

If one side of a window is dark, the light from the bright side will refract strongly through and reflect strongly back into the room.

The person in the room will only see a reflection of themselves and nothing refracted from the other side. In this case, the Girl sees the Boy. The Boy sees his reflection

If one side of a window is dark, the light from the bright side will refract strongly through and reflect strongly back into the room.

The person in the room will only see a reflection of themselves and nothing refracted from the other side. In this case, the Boy sees the Girl. The Girl sees her reflection

If glass is partially coated with a metal like aluminum or silver, the partial reflection is strengthened so that the difference in light intensity is not as important.

This is the principle of a one way mirror

Check out the One Way Mirror Shoe Box

Pre-lab prep

• Last night I built the one-way shoe box as follows:

1) Cut an “I” slit in the middle of both sides of a shoe box.

2) Then cut a viewing hole in both ends

3) Put a Reflect-View in the “I” slit. The top and bottom of the “I” allows the Reflect-View to slide in more easily.

3) Put a Reflect-View in the “I” slit. The top and bottom of the “I” allows the Reflect-View to slide in more easily.

4) Cut a two holes in the lid as shown. These are to let light into one chamber of the box, or the other, or both.

One way mirror show box

Before experiencing the “one-way shoe box”Prepare to answer the following questions on your

worksheet2.1 Before you look through the openings predict

what you think will occur.2.2 What does the viewer with the light see? 2.3 What does the viewer in the dark see? 2.4 Explain, using your knowledge of refraction, the

“one way” quality of this shoe box:

5) Place the lid on the top and view a partner while sliding a cover over one light transmitting hole then the other.

5) Place the lid on the top and view a partner while sliding a cover over one light transmitting hole then the other.

6) A dark, opaque cloth over both you and your partners head improves the effect. It is important that there is very little light on the “dark side”

6) A dark, opaque cloth over both you and your partners head improves the effect. It is important that there is very little light on the “dark side”