Which of the following is based on the study of the shadow cast by the sun?

The correct answer is Sundial

Key Points

• Sundial is the earliest type of time-keeping device, which indicates the time of day by the position of the shadow of some object exposed to the sun’s rays.
• As the day progresses, the sun moves across the sky, causing the shadow of the object to move and indicating the passage of time.
•  It consisted of a vertical stick or pillar, and the length of the shadow it cast gave an indication of the time of day.
• The shadow clock consists of a straight base with a raised crosspiece at one end.
• The base, on which is inscribed a scale of six-time divisions, is placed in an east-west direction with the crosspiece at the east end in the morning and at the west end in the afternoon.
• The shadow of the crosspiece on this base indicates the time