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PhysicsHardMulti concept2019 · 12 Apr Shift 1

Q24.A concave mirror has radius of curvature of 40 cm . It is at the bottom of a glass that has water filled up to 5 cm (see figure). If a small particle is floating on the surface of water, its image as seen, from directly above the glass, is at a distance d from the surface of water. The value of d is close to: (Refractive index of water = 1.33 ) (1) 13.4 cm (2) 8.8 cm (3) 6.7 cm (4) 11.7 cm

What This Question Tests

This complex problem requires applying the concept of apparent depth due to refraction through water, followed by image formation by a concave mirror, and then another refraction at the water surface to find the final image position.

Concepts Tested

Snell's LawApparent depthMirror formulaImage formation by spherical mirrors

Formulas Used

n₁/u + n₂/v = (n₂ - n₁)/R

1/f = 1/v + 1/u

f = R/2

📚 NCERT Sections This Tests

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