Power Lift 4D Redensificador Casmara ® | Envío gratis - La

power 4dA convex lens of power 4D is kept in contact with a concave lens of power 3D, the effective power of combination will be . View Solution; Knowledge Check. A convex lens of focal length 40 cmTwo lenses have power of (i) + 2 d (ii) -4D. What is the nature and focal length of each lens? b. An object is kept at a distance of 100 cm from lens of power -4D. Calculate the image distance.