A convex lens of focal length 40cm is in contact with a concave lens of focal length 25cm . Calculate the power combination ?

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Answer 1 · 2018-02-23T05:39:30

#-0.015#

Power is

#P = 1/f#

The power of combination of the lenses #= P_1 + P_2 + P_3 +....#

#= 1/(f_1) + 1/(f_2) + 1/(f_3) +......#

Therefore

#P = 1/40 + (-1/25)#

# = 1/40 - 1/25#

#=-0.015#