Question

Two thin lense of power+5D and -2D are placed in contact find the power and focal length of combination​

Answer 1

Answer:

Power = 3D focal length =1/3

Explanation:

P1=+5D and P2=-2D so, P1+P2=+3D hence, power of combination = +3D then, f=1/P so, f=1/3m.