_{1}= +10cm and R

_{2}= +8cm.

a) Sketch the lens?

b) Find the focal length?

c) Image distance for an object distance at 15cm?

A certain thin lens made from glass has surfaces with radii R_{1} = +10cm and R_{2}= +8cm. a) Sketch the lens? b) Find the focal length? c) Image distance for an object distance at 15cm? Since both radii are positive, both surfaces are convex. Using lensmaker’s equation Using these values for radii and n = 1.5 for the index of refraction, we can find focal length for this lens f = - 80 cm To find image distance we apply thin lens equation s’ = 12.63 cm This image is virtual, locate 12.63 cm in front of the lens. The effect of the lens is to diverge the incident rays, so that the object appears closer to the lens than it really is. |