When working with circles it is important to recognise and be able to name different parts of the circle. A segment of a circle is an area enclosed by a chord and an arc. What is the name given to a ...

Introduction If you wanted to measure the circumference of Earth, how long would your tape measure have to be? Would you need to walk the whole way around the world to find the answer? Do you think ...

IN Sky and Telescope of September, under the heading “Saluting an Astronomer”, Joseph R. Habes has an article which describes the method adopted by Eratosthenes for measuring the circumference of the ...