Question

A bubble in glass slab $(\mu = 1.5)$ when viewed from one side appears at 5 cm and 2 cm from other side, then thickness of slab is

• A. 3.75 cm
• B. 3 cm
• C. 10.5 cm
• D. 2.5 cm

Answer 1

Answer: (C)

10.5 cm

Answer 2

Total apparent depth,
$y=y_1 +y_2 = 5+2 =7 cm$
If.v is real depth = thickness of slab, then as
$\mu = \frac{real depth}{apparent depth} = \frac{x}{y}$
$\, \, or \, \, x= \mu y = 1.5 \times 7 = 10.5 cm$