Explain to someone who doesn't know any astronomy: (a) why does a horizontal sundial that is built to work in los angeles generally not work in minneapolis, and vice versa? (b) what kind of dial can easily be made adjustable to work at any latitude, and what adjustment does it need?

Explanation:

( a )  It does not work because sundial uses by the image of an object made by the sunlight. As Los Angeles located at western part of united states whereas Minneapolis located at eastern region of united states. Hence, there would be opposite situation for both the places and time reported by sunlight also become opposite.

( b )To work at any latitude, sundial can be made by using gnomon. Generally, horizontal sundial covers 25º to 65º, but on using gnomon it covers additionally 25º and 45º and 45º and 65º.