Science Quiz: Which green line is longer?

Q: Which green line is longer?

A: Both are of the same length. This Ponzo illusion uses the fact that the human brain interprets an image with perspective, which might sometimes be deceiving. You can use a ruler to measure the lines for yourself.

• Credit:

A version of this article appeared in the print edition of The Straits Times on September 25, 2015, with the headline 'ScienceQuiz'. Print Edition | Subscribe