For any rectilinear problem involving constant acceleration, these fundamental equations apply Velocity-Time: Displacement-Time: Velocity-Displacement: Free-Falling Bodies , simply replace acceleration ( ) with gravity ( for downward motion and for upward motion Sample Problems and Solutions 1. The "Return in 10 Seconds" Problem
Stone 2 is thrown 1 second later, so its travel time = t - 1 = 2.193 s. Initial velocity u (downward positive): y = u·t₂ + ½ g t₂² → 50 = u(2.193) + ½ (9.81)(2.193)² ½(9.81)(4.809) = 23.58 Thus 50 = 2.193u + 23.58 → 2.193u = 26.42 → u ≈ 12.04 m/s downward. rectilinear motion problems and solutions mathalino upd