Every circle is 360 degrees Type in the missing degrees Every circle is 360 degrees It takes 2π radii (about 6.28 radii) to travel a full circle. The circumference of a circle is C=2πr If 2π radii are needed for a circle, 1π radii would wrap around C=2πr It takes 2π radii to travel a full circle. full ? half ? a circle. If 2π radii are needed for a circle, 1π radii would wrap around half C=2πr full a circle. π 2π The image above shows it takes about 6.28 radii, or π radii to travel around a circle. An angle of 1 radian cuts off an arc equal to 1 radius. An angle of 2π radians creates a full circle. 2π radians = degrees 1π radian = degrees 180 ? 360 ? Remember, it takes 2π radii to wrap around a circle. It takes 2π radians to travel around a circle. π ? 3π/2 ? π/2 ? initial (start) ray Remember, it takes 2π radii to wrap around a circle. It takes 2π radians to travel around a circle. π 5π/4 ? 3π/4 ? 3π/2 π/2 7π/4 ? π/4 ? start Remember, it takes 2π radii to wrap around a circle. It takes 2π radians to travel around a circle. π 5π/4 3π/4 3π/2 π/2 7π/4 π/4 start π Half a circle has a angle of π radians (180 degrees) start π π/4 radians π/2 radians 3π/4 radians This angle is: start π Half a circle has a angle of π radians (180 degrees) start π π/4 radians π/2 radians 3π/4 radians This angle is: start π Half a circle has a angle of π radians (180 degrees) start π 3π/4 radians 5π/4 radians 7π/4 radians This angle is: start 5π/6 ? 7π/6 ? 11π/6 ? π/6 ? 3π/6 ? throw out the trash choice trash 4π/3 ? 2π/3 ? 5π/3 ? π/3 ? 3π/3 ? throw out the trash choice trash The End |