illusion_ponzo effect 2

[Fu-Kwun Hwang]

Are those two yellow bars the same width?

You can drag more from the top one (Up to 10 bars).

Embed a running copy of this simulation
<applet code='users.ntnu.fkh.illusion_ponzo2_pkg.illusion_ponzo2Applet.class' archive='http://www.phy.ntnu.edu.tw/ntnujava/ejsuser/2/ejs_illusion_ponzo2.jar' name='illusion_ponzo27639' id='illusion_ponzo27639' width='597' height='450' mayscript=true><param name='draggable' value='true'></applet>
Embed a running copy link(show simulation in a popuped window)
<a href='http://www.phy.ntnu.edu.tw/ntnujava/msg.php?smfejs=7639' target='smfejs'>Run simulation</a>

Full screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License

• 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!

The Ponzo illusion is an optical illusion that was first demonstrated by the Italian psychologist Mario Ponzo (1882-1960) in 1913. He suggested that the human mind judges an object's size based on its background. He showed this by drawing two identical lines across a pair of converging lines, similar to railway tracks. The upper line looks longer because we interpret the converging sides according to linear perspective as parallel lines receding into the distance. In this context, we interpret the upper line as though it were farther away, so we see it as longer – a farther object would have to be longer than a nearer one for both to produce retinal images of the same size.

[lookang]

appears to have a problem with the ejs download while the source is correct.

i managed to recompile and attached to share for the benefit of others