Physics, asked by Anonymous, 1 month ago

(i) A plane wavefront approaches a plane surface separating two media. If medium 1 is optically denser and medium 2 is optically rarer, using Huygens’ principle, explain and show how a refracted wavefront is constructed?

(ii)Verify Snell’s law.

(iii)When a light wave travels from a rarer to a denser medium, the speed decreases. Does it imply reduction in its energy? Explain​

Answers

Answered by Anonymous
1

Characters

Aaj koi dikh nhi rha na xD?

Answered by whymona
1

ʜᴇʟʟᴏ ❤️ ᴊʜᴀɴᴅ ʟɪꜰᴇ

(i) When a wave starting from one homogeneous medium enters the another homogeneous medium, it is deviated from its path. This phenomenon is called refraction. In transversing from first medium to another medium, the frequency of wave remains unchanged but its speed and the wavelength both are changed. Let XY be a surface separating the two media ‘1’ and ‘2’. Let v1 and v2 be the speeds of waves in these ᴍᴇᴅɪᴀ.

(ii) Proof of Snell’s law of Refraction using Huygen’s wave theory: When a wave starting from one homogeneous First law: As AB, A' B' and surface XY are in the plane of paper, therefore the perpendicular drawn on them will be in the same plane. As the lines drawn normal to wavefront denote the rays, therefore we may say that the incident ray, refracted ray and the normal at the point of incidence all lie in the same plane. This is the first law of refraction. Second law: Let the incident wavefront AB and refracted wavefront A' B' make angles i and r respectively with refracting surface XY. In right-angled triangle AB' B, Ð ABB' = 90°.

As the rays are always normal to the wavefront, therefore the incident and refracted rays make angles i and r with the normal drawn on the surface XY i.e. i and r are the angle of incidence and angle of refraction respectively. According to equation (3): The ratio of sine of angle of incidence and the sine of angle of refraction is a constant and is equal to the ratio of velocities of waves in the two media. This is the second law ofrefraction , and is called the Snell’s ʟᴀᴡ.

(iii) No. Because energy of wave depends on its frequency and not on its ꜱᴩᴇᴇᴅ.

Similar questions