A lens with focal length produces a sharp image on a screen of an object at distance…
PHYSICS · Subjective · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments
Problem
A lens with focal length f=30cm produces a sharp image on a screen of an object at distance a=40cm from the lens. A plane-parallel glass plate of thickness d=9cm is placed between the lens and object, perpendicular to the optical axis. Through what distance should the screen be shifted to keep the image distinct? The refractive index of the glass is μ=1.8.