Physics Question Helppp

A fish floats in water with its eye at the centre of an opaque walled full tank of water of circular cross section. When the fish look upwards, it can see a fish-eye view of the surrounding scene i.e. it is able to view the hemisphere of the scene above the water surface, and centred at the top of the tank. The diameter of the tank is 30 cm, and the critical angle for water is 48 degrees. At what depth below the surface of the water, d, must the fish be floating?

Spoiler

Reply 1

Zacken

22

Original post by ChronicBoredom

A fish floats in water with its eye at the centre of an opaque walled full tank of water of circular cross section. When the fish look upwards, it can see a fish-eye view of the surrounding scene i.e. it is able to view the hemisphere of the scene above the water surface, and centred at the top of the tank. The diameter of the tank is 30 cm, and the critical angle for water is 48 degrees. At what depth below the surface of the water, d, must the fish be floating?

Spoiler

Sketch the situation and identify the right-angle triangle. tan 48 = opposite/adjacent where adjancent is d and opposite is the radius = diameter/2 = 30/2 = 15.

Reply 2

ChronicBoredom

OP

3

Original post by Zacken

Sketch the situation and identify the right-angle triangle. tan 48 = opposite/adjacent where adjancent is d and opposite is the radius = diameter/2 = 30/2 = 15.