On what principle does sundial work? What is a drawback of a sundial?
The sundial works on the principle that when the sun is at highest point in the sky the image of an object formed by its light is smallest and when it is at the lowest point the image formed is the longest.
- The most major drawback of sundial is that it cannot be used in the night.
- Further it has to be kept outside and cannot be used inside the house or it cannot be wore on a wrist.
- Also, the length of the shadow formed by sunlight is effected by seasons as well and hence it cannot be used to predict the correct time in different seasons.