00:03
A camera is supplied with two interchangeable lenses whose focal links are 35 and 150 millimeters.
00:09
A woman whose height is 1 .6 meters stands 9 meters in front of the camera.
00:15
What is the height of her image on the image sensor as produced by the 35 millimeter and the 150 millimeter lens? okay, so we use our favorite lens equation.
00:26
1 over f is 1 over d .i plus 1 over d .o.
00:31
We also know the magnification is h -i over h -o is negative d -i over d -o.
00:45
So they gave us the focal length.
00:48
Let's go ahead and write them as f1, 0 .035 meters.
00:55
We need to be meters instead of millimeters.
00:59
F -2 is 0 .15 meters.
01:03
The object height is 1 .6 meters, and the object distance is 9 meters.
01:12
So solving for d .i.
01:16
So we have this equation.
01:18
Solve for d .i...