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

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Q: 101 (IAS/2001)

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.

question_subject: 

Science

question_exam: 

IAS

stats: 

0,20,29,22,7,20,0

keywords: 

{'stick undergoes': [0, 0, 1, 0], 'water molecules': [0, 0, 1, 0], 'water': [65, 15, 80, 129], 'surface': [1, 0, 0, 0], 'bent appearance': [0, 0, 1, 0], 'light': [16, 4, 34, 62], 'stick': [0, 0, 1, 0], 'slanting position': [0, 0, 1, 0]}

The correct answer is "A is true but R is false."

When a stick is dipped in water in a slanting position, the phenomenon of refraction occurs. Refraction is the bending of light as it passes from one medium to another medium with a different refractive index. In this case, as light travels from air to water, it bends at the interface between the two mediums.

However, the reason provided, stating that the light undergoes scattering from water molecules, is incorrect. Scattering is a phenomenon where light rays get deflected in different directions due to interaction with particles or molecules in the medium. While scattering can occur in various situations, such as when light passes through a foggy atmosphere or encounters suspended particles, it does not play a significant role in the appearance of a stick dipped in water.

Therefore, assertion A is true because the stick appears short and bent when observed sideways due to refraction. However, reason R is false because the observed effect is not caused by light scattering from water molecules.

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