Circles

If the circumference of a circle is 4*pi*r, what is its radius?

Find the number of revolutions made by a wheel of diameter 1 m in covering a distance of 314 m. (Take pi = 3.14)

If the arc length of a circle is 1/4 of its circumference, what is the angle subtended at the center?

In the figure, O is the center. AB is a diameter. CD is a chord equal to the radius. AC and BD intersect at E. Find angle AEB.

A square of side 8 cm is inscribed in a circle. Find the area of the circle.

Find the area of a circle whose circumference is 22 cm.

What is the perimeter of a sector of a circle of radius 7 cm and angle 90 degrees?

If two tangents inclined at an angle of 60 degrees are drawn to a circle of radius 3 cm, then the length of each tangent is:

If the area of a sector is 1/12 of the area of the circle, find the angle of the sector.

How many points of intersection can a circle and a triangle have at most?

If a chord of length 16 cm is 6 cm away from the center, what is the length of a chord 8 cm away from the center?

What is the radius of the circle passing through the vertices of a right-angled triangle with sides 5, 12, 13?

If the area of a circle is A, and its circumference is C, then which of the following is true?