The image of a candle is formed by a convex lens on a screen. The lower half of the lens is painted black to make it completely opaque. Draw the ray diargram to show the image formation. How will this image be different from the one obtained when the lens is not painted black?

A convergeing lens is used to form an image on a screen.When the upper half of the lens is converd by an opaque screen,

Give the nature, position and size of the image formed by a convex lens when the object lies at 2 F

A concave lens of focal length 15cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw ray diagram.

A convex lens of focal lenght 20 cm is placed coaxially wih a convex mirror of radius of curvature 20 cm.the two are kept at 15 cm apart.A point object lies 60 cm in front of the convex lens.Draw a ray diagram to show the formation of the image by the combination.Determine the nature and position of the image formed.

Draw the ray diagrams and find position,nature and size of image formed by a convex lens,when object is placed:At F.

By giving sign-conventions, derive the lens formula relating object distance, image distance and focal length for a thin convex lens. Draw a ray diagram to show the formation of image of an object placed between optical centre and focus of a convex lens.