Ten Hour Clock Face | Telugu | Hands-On Maths
Channel: Arvind Gupta
Date: 2014-10-30

How do you fold a circle into ten equal sectors to make a ten hour clock face so that each sector is 36-degrees. Take a circle of diameter 15-cm. Fold its diameter and mark it with a pen. The value of this diameter will be 32. Fold at right angles and mark the center. The bottom will be 0, the center 16 and the top will be 32. Fold top to center to locate 24. Fold bottom to 24 to locate 12. Fold the top to 12 to locate 27. Finally place top to 27 to locate the point. Draw a line. This point will be 11 from the center. Fold the diameter and mark it with dotted lines. Fold the edge of the circle to the center. Fold both tips and this will locate point P. The height of the dotted line will be 11/32 and its base will be 8/32. The angle from P to centre and the right will be 54-degrees. Tan inverse 11/8 is roughly equal to 54-degrees. Mark the diameter passing through P and O. Extend the hypotenuse of the triangle to get the second point. The sectors can be easily bisected to get the midpoints. In this way you will be able to divide the circle into 10-equal parts. Each internal angle will be 36-degrees. Now you can see the circle divided into ten equal sectors. This work was supported by IUCAA and Tata Trust. This film was made by Ashok Rupner TATA Trust: Education is one of the key focus areas for Tata Trusts, aiming towards enabling access of quality education to the underprivileged population in India. To facilitate quality in teaching and learning of Science education through workshops, capacity building and resource creation, Tata Trusts have been supporting Muktangan Vigyan Shodhika (MVS), IUCAA's Children’s Science Centre, since inception. To know more about other initiatives of Tata Trusts, please visit www.tatatrusts.org