Assertion (A) : A stick is dipped in water in a slanting position. If observed sideways, the stick appears short and bent at the surface of water. Reason (R) : The light coming from the stick undergoes scattering from water molecules giving the stick a short and bent appearance.

The assertion is correct: a stick (or pencil) partly immersed in water appears bent and its submerged portion appears displaced/shortened because light from the submerged part changes direction at the air–water interface, so the apparent position differs from the real one [1]. The reason given is incorrect: scattering (light being re‑directed by molecules or particles) is a different process that redistributes light into many directions and does not produce the coherent apparent displacement at a smooth interface described here [2]. The observed bending is explained by refraction — the change in direction of a ray crossing media of different refractive indices as given by Snell’s law — and not by molecular scattering [3].

Sources

1. [1] Science , class X (NCERT 2025 ed.) > Chapter 9: Light – Reflection and Refraction > 9.3 REFRACTION OF LIGHT > p. 145
2. [2] https://www.sciencedirect.com/topics/engineering/scattering-phenomenon
3. [3] Science , class X (NCERT 2025 ed.) > Chapter 9: Light – Reflection and Refraction > Activity 9.10 > p. 148