Download presentation

Presentation is loading. Please wait.

Published byGarey Stephens Modified over 2 years ago

1
The Roget Illusion and the Persistence of Vision by J. L. Hunt Dept. of Physics Univ. of Guelph

2
Peter Mark Roget (1779-1869) the author of the famous Thesarus noticed an unusual illusion

3
When a carriage wheel rolls behind A picket fence (palisade) it does NOT look like this

4
It looks like……..

5
Which is known as The Roget (Palisade) Illusion THIS!!!

6
A simple apparatus demonstrates the illusion. An endless palisade Is turned by a crank and a fixed wheel rolls behind it.

7
Here’s what you see looking at the rolling wheel through the palisade

8
Let’s follow the intersection of a spoke and a slit as the wheel rotates and the array of slits moves across.

10
This is one of the few illusions that can be analyzed mathematically. The x and y coordinates of the spoke and slit intersection are: x = r t y = x tan [2 n /N + x/r] Where r = radius of the wheel = angular velocity of the wheel N = number of spokes in the wheel n = 0……(N-1) is an index of a particular spoke.

Similar presentations

OK

Warm Up Plane A is spotted on a rectangular tracking screen, by an air traffic controller at (420,0) flying west 2 miles and north 3.2 miles each minute.

Warm Up Plane A is spotted on a rectangular tracking screen, by an air traffic controller at (420,0) flying west 2 miles and north 3.2 miles each minute.

© 2017 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Free download ppt on brain machine interface Ppt on electrical power in india Ppt on management of water resources Ppt on linear programming in operations research Best ppt on earth day by alex Ppt on political parties and electoral process of japan Good manners for kids ppt on batteries Ppt on ministry of corporate affairs goi Ppt on forward rate agreement explain Ppt on history of olympics for kids