Question

A lens x has a focal length of 20cm and a lens y has a focal length of 40cm which lens would you select to obtain a more convergent beam of light

Answer 1

Answer:

Hi Ira

Focal length of any lens is the point where light converges.so,if focal length is more then the lens has coverged the light to a larger distance that is it has coverged less.Whereas,if the focal length is less then the light is coverged at a smaller distance that is coverged more.

so, we can affirm that lens of 20cm should be used to coverged light to a larger extent.