To determine the vertical velocity of an object thrown downwards after 2.0 seconds, we need to consider the acceleration due to gravity, which is approximately 9.8 m/s² near the surface of the Earth.
When an object is thrown downward, its initial velocity (u) is 23 m/s, and the acceleration due to gravity (a) is -9.8 m/s² (negative because it acts in the opposite direction of the initial velocity).
Using the formula for velocity in vertical motion:
v = u + at
where: v = final velocity u = initial velocity a = acceleration t = time
Plugging in the given values:
v = 23 m/s + (-9.8 m/s²) * 2.0 s
v = 23 m/s - 19.6 m/s
v = 3.4 m/s
Therefore, the vertical velocity of the object thrown downwards after 2.0 seconds is 3.4 m/s.