### Author Topic: periscope  (Read 27355 times)

#### Fu-Kwun Hwang

• Hero Member
• Posts: 3062
##### periscope
« on: December 05, 2009, 12:11:25 pm »
A periscope is an instrument for observation from a concealed position. In its simplest form, it is a tube in each end of which are mirrors set parallel to each other at 45 degree angle.

The size of the image is the same as the object.

The questions is: What will happen if the object is moving up?
a. The image will move up, too!
b. The image will stay at the same height.
c. The image will move down.

Make a guess before you play with it and find out the answer by yourself.

-*-

The following is a simulation for periscope (with two flat mirrors).
Click trace checkbox to view the trace of light path (which form the image)
You can drag the object at the top right position with your mouse and watch how the light paths changed.

Full screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
• Please feel free to post your ideas about how to use the simulation for better teaching and learning.
• Post questions to be asked to help students to think, to explore.
• Upload worksheets as attached files to share with more users.
Let's work together. We can help more users understand physics conceptually and enjoy the fun of learning physics!

For the following case: the same question again

What will happen if the object is moving up?
a. The image will move up, too!
b. The image will stay at the same height.
c. The image will move down.

#### lookang

• Hero Member
• Posts: 1774
• http://weelookang.blogspot.com
##### Re: periscope
« Reply #1 on: December 05, 2009, 09:14:17 pm »
the model used to simulate the periscope seems to need some more refinement.
the bug is attached.