question_answer

The speed of projectile at its maximum height is half of its initial speed. The angle of projection is

A) \[{{60}^{o}}\]                     

B) \[{{15}^{o}}\]         

C) \[{{30}^{o}}\]            

D) \[{{45}^{o}}\]                     

Correct Answer: A

Solution :

Conserving the horizontal component component of the projectile, in context to figure, we get \[v=u\cos \theta \] \[\frac{u}{2}=u\cos \theta \Rightarrow \cos \theta =\frac{1}{2}\]or \[\theta ={{60}^{o}}\] Hence, the correction option is (a).