Problem 34.5: Size of a fish's world

Please wait for the animation to completely load.

A fish in a tank is shown. Both the position of the source and the angle of the source rays can be adjusted by click-dragging the circular hotspots. You can use the movable green protractor and click-drag to measure angles (position is given in centimeters and angle is given in degrees). Restart.

  1. When the fish's eye is 1 cm from the edge, how big is the circle through which the fish sees the world outside the fish tank when he looks straight ahead (to the right in the animation)?
  2. Find an expression for the size of the circle through which the fish sees the outside world as a function of how far away the fish is from the right edge of the tank.

Problem authored by Melissa Dancy.