In your laboratory you trace the path of light rays through a glass slab for different values of angle of incidence (Li) and in each case measure the- values of the corresponding angle of refraction (Lr) . and angle of emergence (Le). Other basis of your observations your correct conclusion is:

To determine the approximate value of the focal length of a given concave mirror, you

focus the image of a distant object formed by the mirror on a screen. The image obtained on the screen, as compared to the object is always:

Suppose you have focused on a screen the image of candle flame placed at the farthest end of the laboratory table using a convex lens. If your teacher suggests you to focus the parallel rays of the Sun, reaching your laboratory table, on the same screen, what you are expected to do is to move the:

In the following ray diagram the correctly marked angles are:

A student adds a spoon full of powdered sodium hydrogen carbonate to a flask containing ethanoic acid. List two main observations, he must note in his note book, about the reaction that takes place. Also write chemical equation for the reaction.