Focal length -physics

• bonkysleuth

  13 Nov 08, 23:36

  http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=48

   

  Please help me check the unit for the focal length in this virtual lens image. It does not state the unit.thanks.

• skythewood

  13 Nov 08, 23:38

  focal length unit should be metre, SI unit.

• bonkysleuth

  13 Nov 08, 23:46

  Originally posted by skythewood:

  focal length unit should be metre, SI unit.

  
  thanks. an instruction told me to click on the lens and make focal length shorter. What happens to the shape of the lens?

   

  I found that no matter where I drag the length, focal length remains the same. is there anything I can do to adjust focal length(If you tried the programme, that is)