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Applied Mathematics · Ch 2 — Numerical Applications

Clock and Calendar

2.3

Clock and Calendar

Time is the most universal measure we use, yet its units — seconds, minutes, hours — are entirely human inventions. A clock is simply a device that counts these units, while a calendar organises them into days, months, and years based on the Earth's motion around the Sun. In this section, we will learn how to calculate the angle between the hands of a clock at any given time, and how to find the day of the week for any given date using the concept of odd days. These skills are not just exam favourites — t …

Figure 2.1A clock face at 3:00 showing the hour hand at 3 and minute hand at 12 with the 90 degree angle between them marked
Fig. 2.1 — A clock face at 3:00 showing the hour hand at 3 and minute hand at 12 with the 90 degree angle between them marked

Drawn by us to help you understand the concept clearly, and verified to make sure it's accurate. For exams, practice from your NCERT textbook's own diagram.

At 3:00 the hands are 90° apart — the basis of clock-angl …

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