Q.

A particle moving in a circle of radius R with uniform speed takes time T to complete one revolution. If this particle is projected with the same speed at an angle θ to the horizontal, the maximum height attained by it is equal to 4R. The angle of projection θ is then given by                                [2024]

1 sin-1[2gT2π2R]12  
2 sin-1[π2R2gT2]12   
3 cos-1[2gT2π2R]12  
4 cos-1[πR2gT2]12   

Ans.

(1) 

       2πRT=v

       Maximum height H=v2sin2θ2g

       4R=4π2R2T22gsin2θ

       sinθ=2gT2π2Rθ=sin-1(2gT2π2R)12