What is the rock's speed after 3 seconds, in m/s, if it encounters no air resistance? ... Well, we can use the falling objects equation, which states that. d=12>2. where g is the gravitational acceleration, t is the time in seconds. So, plugging in values into the equation, we get. d=12⋅9.81 m/s2⋅9 s2.
Explanation: