Question

a fish is seen from one side of a fish tank it appears to be at a distance of 12 cm from the glass when seen from the opposite side it appears to be at 15 cm from that side.find the width of the tank if refractive index of water is 4/3.ignore the effect of glass wall

Answer 1

Answer:

20.25 cm.

Explanation:

Apparent Position = Real position ÷ Refractive index of water with respect to refractive index of air.

Case 1:

Apparent Position = 12 cm.

Refractive index of water with respect to refractive index of air = Refractive index of air ÷ refractive index of water.

====> 1 ÷ 4/3.

= 3/4.

Therefore,

Real position = 12*3/4 = 9 cm.

Case 2:

Apparent Position = 15 cm.

Therefore,

Real position = 15*3/4 = 45/4 = 11.25 cm.

Width of tank( ignoring width of fish) = Real position of fish in Case 1 + Real position of fish in Case 2.

= 9 + 11.25 = 20.25 cm

Answer : 20.25 cm.

Hope this helps!!!! Please do mark me BRAINLIEST if you think the answer is worth it ☺️.

Answer 2

Answer:

36 cm

Explanation:

Real depth/apparent depth = air μ water

∴ RD/12 = 4/3

∴RD = 12×4/3 = 16 cm.

RD/AD = air μ water

∴RD = 15×4/3 = 20 cm.

∴Thickness of tank = 20 + 16 = 36 cm