Since a circle has no sides its perimeter also known as its circumference is the length of the circles exterior. Calculate the perimeter of a semicircle of radius 1. Then multiply by 2 to get the diameter.
If you find the distance between the two given points you will have the diameter of the circle.
As the perimeter of a circle is 2pr or pd. The 1 2 and 2 cancel each other out so you can simplify to get this perimeter of a semicircle formula. Semi-circle is exactly half of a complete circle then its circumference or perimeter should also be half of the circumferenceperimeter of circle of a complete circle it is so but a semicircle has some part of its periphery in form of straight line so circumference or more precisely in case of semi-circle perimeter is. Find the circumference of the circle.