Question
An object is 30.0 cm to the left of a convex lens with a focal length of +8.0 cm. Calculate the distance from the lens. Would it be upright or inverted?
Answers
Anonymous
Use 1/f=1/di + 1/do
and
Magnification M=hi/ho=-di/do
Use metres throughout
do=0.30
f=+0.08 m (converging lens)
di=1/(1/f-1/do)
=0.1091 (image distance)
So image is real (di >0) and on the right-hand (emerging) side of the lens.
M=-di/do=-0.364
(image smller, inverted, M<0)
and
Magnification M=hi/ho=-di/do
Use metres throughout
do=0.30
f=+0.08 m (converging lens)
di=1/(1/f-1/do)
=0.1091 (image distance)
So image is real (di >0) and on the right-hand (emerging) side of the lens.
M=-di/do=-0.364
(image smller, inverted, M<0)