where can i get the basic concept of Mueller-Lyer experiment in psychology?

Answer 1

The link below is an example of a test from a psych department at Cal State, Fullerton.

The second one is from a different school and includes an explanation. It debates the use of angled fins comparing to angled fins of a different angle or comparing angled fins to a line with no fins.

Answer 2

Try looking it up on the internet.
:o)
Jerry