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

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Solution

Given,
Refractive index of the glass block, $μ_{g} = 1.5$
Shift in the image = $7 m m$ or $0.7 c m$
Thickness of glass block or real depth = ?
Shift = Real depth $\times (1 - \frac{1}{μ})$
$0.7 = R \times (1 - \frac{1}{1.5})$

$R = \frac{0.7 \times 1.5}{0.5} = 2.1 c m$ .

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

Given,Refractive index of the glass block, μg=1.5Shift in the image = 7mm or 0.7cmThickness of glass block or real depth = ?Shift = Real depth ×(1−1μ)0.7=R×(1−11.5)R=0.7×1.50.5=2.1cm.

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

Given,
Refractive index of the glass block, $μ_{g} = 1.5$
Shift in the image = $7 m m$ or $0.7 c m$
Thickness of glass block or real depth = ?
Shift = Real depth $\times (1 - \frac{1}{μ})$
$0.7 = R \times (1 - \frac{1}{1.5})$

$R = \frac{0.7 \times 1.5}{0.5} = 2.1 c m$ .