A point in lens through which light passes undeviated is called the centre of curvature.

The substance through which light can pass is called -

The materials through which light can easily pass are called-

Which cell organelle is called cell centre?

What is the angle of incidence ,when a ray of light falls on the spherical mirror from its centre of curvature?

In a plane there are 37 straight lines, of which 13 passes through the point A and 11 passes through point B. Besides, no three lines passes through one point no line passes through both points A and B and no two are parallel, then find the number of points of intersection of the straight line.

Two points A and B are 16 cm apart. A circle with radius 17 cm is drawn to pass through these points. Find the distance of AB from the centre of the circle.

The differential equation of circles passing through the points of intersection of unit circle with centre at the origin and the line bisecting the first quadrant, is

A ray of light is sent through the point P(1,2,3) and is reflected on the XY plane. If the reflected ray passes through the point Q(3,2,5) then the equation of the reflected ray is