A piece of paper in the shape of a sector of a circle (see Fig.1) is rolled up to form a right-circular (see Fig. 2). The value of the angle `theta` is

A piece of paper in the shape of a sector of a circle (see Fig. 1) is rolled up to form a right- circular cone (see Fig. 2). The value of the angle theta is.

A piece of paper is in the form of a sector, making an angle a. The paper is rolled to form a right circular cone of radius 5 cm and height 12 cm. Then the value of angle a is

From a piece of paper in the shape of a regular hexagon, sectors of circles with the centre at the vertices are removed as shown in the figure. Find the fraction of the vertices are removed as shown in the figure. Find the fraction of the piece of paper left. Also find the perimeter of the piece of paper left in terms of a side of the hexagon

From a piece of paper in the shape of a regular hexagon, sectors of circles with the centre at the vertices are removed as shown in the figure. Find the fraction of the vertices are removed as shown in the figure. Find the fraction of the piece of paper left. Also find the perimeter of the piece of paper left in terms of a side of the hexagon

A semi-circular plate is rolled up to form a conical surface. The angle between the generator and the axis of the cone is

In fig. , b is more than one-third of a right angle than a. The values of a and b are :

In fig. , b is more than one-third of a right angle than a. The values of a and b are :

Prove that the area of a sector of circle with radius r and central angle theta^@ is 1/2 r^2 theta .

ABCD is a cyclic quadrilateral (see Fig.). Find the angles of the cyclic quadrilateral.