Q.

Projectiles A and B are thrown at angles of 45° and 60° with the vertical, respectively, from the top of a 400 m high tower. If their ranges and times of flight are the same, the ratio of their speeds of projection vA:vB is          [2024].

1 1:3  
2 2:1  
3 1:2  
4 1:2  

Ans.

(4)

RA=RB

(VAcos45°)T=(VBcos60°)T

VA2=VB2

VAVB=22=12