Q.
A projectile is thrown with an initial velocity (ai^+bj^)m/s, where i^ and j^ are the unit vectors along horizontal and vertical directions respectively. If the range of projectile is twice the maximum height reached by it, then
Given initial velocity, u=ai^+bj^ ∴ux=a,uy=b
Time of flight, T=g2uy=g2b
Maximum height, H=2guy2=2gb2
Range, R=g2uxuy=g2ab ∵R=2H (Given) ∴g2ab=2×2gb2
or 2a=b