Grade 12General Physics
Two lens of power 15D and 5D are placed is contact co-axially. The focal length of equivalent lens is?
1 Answer
Arun
Power=1/focal length(meters)
Combining two lens
Power is additive(if the lenses are thin)
so combined power is
-10D -10=1/f
hence
f=-0.1m=-10cm
Regards
Arun (askIITians forum expert)
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