Angles and Trigo

A horse is tied to a post by a rope. If the horse moves along a circular path, always keeping the rope tight and describes 88 meters when it traces the angle of 72o at the centre, then the length of the rope is

• 70m

• 55m

• 40m

• 35m

A pendulum of 14cms long oscillates through an angle of 12o, then the angle of the path described by its extrimities is

• $\frac{13\pi}{14}$

• $\frac{14\pi}{13\ }$

• $\frac{15\pi}{14}$

• $\frac{14\pi}{15}$

The central angle of a sector of circle of area 9π sq.cm is 600, the perimeter of the sector is

• $\pi$

• $3+\pi$

• $6+\pi$

• 6

20 meters of wire is available for fancing off a flower-bed in the form of a circular sector of radius 5 meters, then the maximum area (in sq. m.) of the flowerbed is

• 15

• 20

• 25

• 30

 $\frac{22\pi}{15}$  = ____ degrees

• 246

• 264

• 224

• 426

 $156^0=$  

•  $\frac{17\pi}{15}$  

•  $\frac{13\pi}{15}$  

•  $\frac{11\pi}{15}$  

•  $\frac{7\pi}{15}$  

A semicircle is divided into two sectors whose angles are in the ratio 4:5. Find the ratio of their areas?

• 5:1

• 4:5

• 5:4

• 3:4

If the angles of a triangle are in the ratio 1:2:3, then the smallest angle in radian is

• $\frac{\pi}{3}$

• $\frac{\pi}{6}$

• $\frac{\pi}{2}$

• $\frac{\pi}{9}$

Find the number of sides of a regular 
 polygon if each of its interior angle is  $\frac{3\pi}{4}$  

• 6

• 7

• 8

• 9

The value of tan1°.tan2°tan3°..... tan89° is equal to

• -1

• 1

• $\frac{\pi}{2}$

• $2$