Light – Reflection and Refraction PDF

travel in the same direction in all media. It appears that when travelling obliquely from one medium to another, the direction of propagation of light in the second medium changes. This phenomenon is known as refraction of light. Let us understand this phenomenon further by doing...

travel in the same direction in all media. It appears that when travelling obliquely from one medium to another, the direction of propagation of light in the second medium changes. This phenomenon is known as refraction of light. Let us understand this phenomenon further by doing a few activities. Activity 9.7 n Place a coin at the bottom of a bucket filled with water. n With your eye to a side above water, try to pick up the coin in one go. Did you succeed in picking up the coin? n Repeat the Activity. Why did you not succeed in doing it in one go? n Ask your friends to do this. Compare your experience with theirs. Activity 9.8 n Place a large shallow bowl on a Table and put a coin in it. n Move away slowly from the bowl. Stop when the coin just disappears from your sight. n Ask a friend to pour water gently into the bowl without disturbing the coin. n Keep looking for the coin from your position. Does the coin becomes visible again from your position? How could this happen? The coin becomes visible again on pouring water into the bowl. The coin appears slightly raised above its actual position due to refraction of light. Activity 9.9 n Draw a thick straight line in ink, over a sheet of white paper placed on a Table. n Place a glass slab over the line in such a way that one of its edges makes an angle with the line. n Look at the portion of the line under the slab from the sides. What do you observe? Does the line under the glass slab appear to be bent at the edges? n Next, place the glass slab such that it is normal to the line. What do you observe now? Does the part of the line under the glass slab appear bent? n Look at the line from the top of the glass slab. Does the part of the line, beneath the slab, appear to be raised? Why does this happen? 9.3.1 Refraction through a Rectangular Glass Slab To understand the phenomenon of refraction of light through a glass slab, let us do an Activity. 146 Science 2024-25