# what is the radius of a circle

Dimensions of a Circle. Radius of a circle when circumference is given calculator uses. What is Radius of a circle when circumference is given? Click on "show diameter". The formula is C=2πr{\displaystyle C=2\pi r} , where C{\displaystyle C} equals the circle’s circumference, and r{\displaystyle r} equals its radius. A circle is a shape with all points at the boundary having the same distance to the centre. In the figure above, drag the orange dot around and see that the radius is always constant at any point on the circle. The area of a circle is the space it occupies, measured in square units. Enter any single value and the other three will be calculated. The plural form is radii (pronounced "ray-dee-eye"). For a circle, three lengths most commonly are applied: The radius – defined above Step 3: Let us say that OB meets the circle in C. Proof. $$(y-0)^2 + (x-0)^2 = 1^2 \\ y^2 + x^2 = 1$$ Practice 2. How to calculate Radius of a circle when circumference is given? In other terms, it simply refers to the line drawn from the center to any point on the circle. A circle is a set of all points in a plane that are all an equal distance from a single point, the center. The radius of a circle when the circumference is given is the distance from the center outwards provided the value of circumference is given is calculated using. Circumference of a circle is the enclosing boundary of that circle. Circumference of Circle is the distance all the way around the circle. Area of a circle segment (given central angle), Area of a circle segment (given segment height), Basic Equation of a Circle (Center at origin), General Equation of a Circle (Center anywhere), Radius of an arc or segment, given height/width. The area, diameter and circumference will be calculated. Therefore, the radius and the area of the circle are 5 cm and 78.5 cm 2 respectively. Problem Answer: The radius of the circle is 5. A diameter is just two radiuses drawn in opposing directions from the circle's origin. See Answer. In classical geometry, a radius of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length.The name comes from the Latin radius, meaning ray but also the spoke of a chariot wheel. The Electric Flux Through The Circle When Its Face Is 45° To The Field Lines Is 74.49 Nm2/C. The circumference is the distance around the edge of the circle. or, when you know the Circumference: A = C2 / 4π. The distance between any point of the circle and the centre is called the radius. If the diameter ( d) is equal to 10, you write this value as d = 10. Sometimes the word 'radius' is used to refer to the line itself. Expert Answer . Hence AB = 2 × 10 ⇒ AB = 20 cm. Diameter (d): Diameter is the length of the line that passes across the circle through the center of the circle. A circle of radius = 12 or diameter = 24 or circumference = 75.4 mm has an area of: 4.524 × 10 -10 square kilometers (km²) 0.0004524 square meters (m²) 4.524 square centimeters (cm²) (a) What is the electric flux through the disk? How many ways are there to calculate Radius? 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