A converging lens of focal length f produces a virtual image of a real object when the object is?

a- closer than f from the lens


b- at the distance f from the lens


c- farther than f from the lens


d- at any distance from the lens

A converging lens of focal length f produces a virtual image of a real object when the object is?
Hi Use all the rules you know about optics.





1. paralel lines to main axis -%26gt; intersests focal point on other side(and vice versa)


2. rays going through opical center go straight through.





Real images are formed by "real rays" .Virutal images are formed by extending the lines "backwards". These may or may not meet somewhere.


Draw the situations for the object behind to f. on the f (extend backwards) . between f and optical center (ext. backwards)





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another interesting rule (which has got nothing to do with your quesition.) is that parallel lines on one side of the lens meet at the other side at one point on the focal line (somewhere perpendicular to the focal point)