Light from a piont source in air falls on a convex spherical glass surface (
)
Calculate the position of the image when the light source is 1 m from the glass surface.
What curvature must be given to the concave refractive surface(
) for a virtual image at 40 cms
of an object in this medium at a distance of 60 cms, the adjoining medium being air
Find the focal length of a double concave lens of radius of curvature 20 cms each and (
)
placed in air
Two thin leenses are in contact and the focal length of the combination is 80 cms. If the focal length of one of
one lens is 20 cms , what is the power the other ;
The focal length of a lens for red is Fr, for green is Fg, and for blue is Fb.Which statement is correct :
Two convex lenses focal lengths F1 and F2 are placed at a distance. A beam incident parallel to th principal
axis emerges from the combination as parallel.The distance between the lenses is;
A biconvex lens of focal length f forms an image of the same size as the object. the distance between the object and the image is
A plaino convex lens of glass , of refractive index 3/2 has a focal length F and radius of curvature R. Then ;
An equiconvex lens has power P. It is cut in to two equal halves along the vertical plane. The power each half is :
An equiconvex lens of refractive index 5/3 and focal length 15 cms in air is placed in a liquid of refractive index 4/3
The focal length of the lens becomes;