मराठी

A postage stamp kept below a rectangular glass block of refractive index 1.5 when viewed from vertically above it, appears to be raised by 7.0 mm. Calculate the thickness of the glass slab. - Physics

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प्रश्न

A postage stamp kept below a rectangular glass block of refractive index 1.5 when viewed from vertically above it, appears to be raised by 7.0 mm. Calculate the thickness of the glass slab.

संख्यात्मक

उत्तर

Refractive index of glass = 1.5

Let the thickness of slab = x mm

stamp raised by = 7 mm

∴ observed depth. = (x - 7) mm

R.I = `"Real depth"/"observed depth"`

= `3/2 = x/((x - 7))`

∴ 3x - 21 = 2x

Or x = 21 mm = 2.1 cm

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पाठ 4: Refraction of Light at Plane Surfaces - Exercise 4 (C) 3 [पृष्ठ ९२]

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सेलिना Physics [English] Class 10 ICSE
पाठ 4 Refraction of Light at Plane Surfaces
Exercise 4 (C) 3 | Q 3 | पृष्ठ ९२

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