...-~i2t == 3456, is the circular measure of an angle of 60°; therefore, 3456 = 57-6, is the value of the angle subtended at the centre of a circle by an arc equal to radius. We obtain the same result in the following way : — 360° x 60 — 2 1 600, = the circumference...

...fraction of four right angles, which is constant, whatever may be the radius of the circle. 210. Since the angle subtended at the centre of a circle by an arc which is equal to the radius is an invariable angle it may be taken as the unit of angular measurement,...

...feet, makes 15 revolutions per minute. How many miles per hour does the end of the sail traverse Î 21. The angle subtended at the centre of a circle by an arc equal to the radius of the circle is the same for all circles. Let 0 be the centre of a circle, whose radius...

...numerical value of an angle, it is more suitable and it is usual to represent the angle by its ratio to the angle subtended at the centre of a circle by an arc equal to the radius. This angle (Chap. i. Prop. i. Cor. 2) is invariable, that is, is the same whatever radius...

...The grade, which is the one-hundredth part of a right angle. III. The unit of circular measure, which is the angle subtended at the centre of a circle by an arc equal in length to the radius. DBF. The circular measure of an angle is the number expressing the ratio of the angle to the angle...

...[Arithmetic. See page 9.] [Specimen Page, No. 5.] 14 ON THE MEASUREMENT OF ANGLES. 28. To shew that the angle subtended at the centre of a circle by an arc equal to the radius of the circle if the same for all circles. Let 0 be the centre of a circle, whose radius...

...\Arithmctic. See fage 9.] [Specimen Page, No. 5-] 14 ON THE MEASUREMENT OF ANGLES. 28. To shew tJiat the angle subtended at the centre of a circle by an arc equal to the radius of the circle is the lame for all circles. Let 0 be the centre of a circle, whose radius...

...£1239 . li . 8 = £2. i%s. 4^. each. : Page, No. 5.] 14 ON -THE MEASUREMENT OF ANGLES. 28. To shew that the angle subtended at the centre of a circle by an arc equal to the radius of the circle it the same for all circlet. Let 0 be the centre of a circle, whose radius...

...8= £2. 18s. ¿4- each. [Arithmetic. See page 9.] 14 Off THE MEASUREMENT OF ANGLES. 28. To shew that the angle subtended at the centre of a circle by an arc equal to the radius nf the circle is the same for all circles. Let 0 be the centre of a circle, whose radius...

...numerical value of TT to five decimal places, calculate, to the nearest integer, the number of seconds in the angle subtended at the centre of a circle by an arc of length equal to that of the radius of the circle. 11. Assuming the fundamental trigonometrical formulae...