Light Reflectio...

A real object is placed in front of a convex lens of focal length $$f$$ at its principal focus. Then the image is formed at

A concave mirror gives an image three times as large as the object placed at a distance of 20 cm from it. For the image to be real, the focal length should be.

An object 1 cm tall is placed 4 cm in front of a mirror. In order to produce an upright image of 3 cm height, one needs a

Find the size of the image formed by a spherical mirror from the following data :
$$u = -20\ cm$$, $$f = -15\ cm$$ and height of object $$= 1.0\ cm$$

Focal length of a convex lens is $$20 cm$$ and its RI is $$1.5$$. It produces an erect, enlarged image if the distance of the object from the lens is

A ray of light strikes a glass plate at an angle of $${60}^{o}$$. If the reflected and refracted rays are perpendicular to each other, the refractive index of glass is

When rays of light are incident on a glass slab, then the incident ray and emergent ray are _________ to each other.

Observe the given figure and name the following rays:

A glass slab is placed in the path of convergent light. The point of convergence of light :

The distance between principal focus and optical center of the lens is ________.