An object is launched horizontally from a height of 45 m above the ground with a speed of 10 m/s. The time at which the object will hit the ground is : (Take g = 10 m/s²)

In horizontal projectile motion, the time of flight depends only on the vertical drop. Using h = (1/2)gt², we get 45 = (1/2)(10)t², so t² = 9, giving t = 3 s. The horizontal velocity of 10 m/s does not affect the time taken to reach the ground. Therefore the object hits the ground after 3 seconds.