Here is a ray ` overline(OA)`. It starts at O and passes through the point A. It also passes through the point B. Can you name it as `overline(OB)`? Why? Can you write the ray ` overline(OA)` as ` overline(AO)`? Why? Why not? Give reasons.

Take four points A, B, C and D such that A B, C lie on the same line and D is not on it. Can the four line segments overline AB , overline BC , overline CD , and overline AD from a quadrilateral? Give reason.

What happens to a ray which passes through focal point and falls on the concave mirror and also draw the ray diagram.

A strainght line L with negative slope passes through the point (1,1) and cuts the positve coordinates axes at the points A and B . If O is the origin , thene the minimum value of OA+OB as L varies , is

If the light ray is passing through the centre of curvature of a concave mirror, it doesn't deviate. Why ?

Take a graph paper, plot the point (2, 4) and draw a line passing through it. Now answer the following questions : Can you draw another line that passes through the point (2, 4)?

Take a graph paper, plot the point (2,4), and draw a line passing through it. Now answer the following questions. Can you draw another line that passes through the point (2,4).

Take a long cylindrical copper tube. Hold it so that it is perpendicular to the horizontal. A stone and a bar magnet are left freely, so that bar magnet passes through the tube and stone outside the tube. Which one reaches the earth first. Guess why it is so ? Give proper reasons.

Can you guess now, why light splits into different colours when it passes through a prism ?

State whether the following statements are true or false? Also give reasons for your answers : Only one line can pass through a given point.