SACE Stage 2 Physics — Motion 1.1

Independence of Velocity Components

A ball dropped from rest and a ball launched horizontally from the same height fall together — reaching the ground at exactly the same time. Gravity acts identically on both; only horizontal motion differs.

Mode

Launch height m

Horizontal speed m/s

Guiding lines

Velocity components

Landing times

Key idea

Vertical motion depends only on gravity — not on horizontal velocity. Both balls experience the same downward acceleration g, so at every instant they share the same height. The launched ball's horizontal motion is completely independent: it travels at constant v_h while falling, unaffected by gravity.

t = 0.00 s