Answer to Question #10607 in Mechanics | Relativity for Ryan Dutton
An object is dropped from a platform 400 ft high. Ignoring wind resistance, how long will it take to reach the ground?
Let's admit that 400 ft = 121.92 m. So,
t = √(2H/g) = √(2·121.92/9.8) ≈ 4.9881 s.