A non-flying ant wants to travel from the bottom corner to the diagonally opposite top corner of a cubical room. The side of the room is 2 meters. What will be the minimum distance that the ant needs to travel?
The shortest route ant takes to travel from the bottom corner to the diagonally opposite top corner is shown below.
The route goes through lateral faces (vertical faces) of the cubical room.
The length of route, r = $$\sqrt{\ \left(2+2\right)^2+2^2}$$ = $$\sqrt{\ 20}$$ = $$2\sqrt{5}$$