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 angle A B O space equals space 30 degree. space PQ is parallel to OA

Based on the above information answer the following questions:

 

(iii) (a) Find the length of AP

1 7532cm  
2 7542cm  
3 -7534cm  
4 7632cm  

Ans.

(1)

Since the radius of circle is perpendicular to the tangent at the point of contact  OAP = 90°

Since PQ  OA OAP = QPB = 90° (Corresponding angles)Now, OB = 150 cmOQ+QB=15075+QB=150QB=150-75=75 cmIn right ΔPBQ,cos30°=PBQB32=PB75PB=7532cmAP=AB-PB=753-7532AP=7532cm