Q.

The discus throw is an event in which an athlete aims to throw a discus as far as possible. The athlete spins counterclockwise one and a half times within a circle before releasing the discus. Upon release, the discus travels along a tangent to the circular path of the spin.

In the given figure, AB is one such tangent to a circle of radius 75 cm. Point O is centre of the circle and ABO = 30°.  PQ is parallel to OA

Based on the above information answer the following questions:

 

(i) Find the length of AB.

 

1 753 cm  
2 752 cm  
3 653 cm  
4 -753 cm  

Ans.

(1)

Since OA is radius and BA is tangent to the circle at point A

 OAB = 90°In ΔOAB,tan30°=OAAB13=75AB AB=753 cm