A ball is thrown straight up with a velocity of 16 m/s; what will be its velocity 2.0s after being released?

The ball will be travelling downward with a speed of 9.8 m/s.

Explanation:

The ball will be travelling downward with a speed of 9.8 m/s.

Explanation:

The acceleration of the ball will be a constant  

9.8 m s 2

(downward), regardless of whether the ball is travelling upward or downward.

The equation that makes this calculation simplest is

v f = v i − g ( Δ t )  

where the negative sign has been used to account for the opposite directions of  v i  and  g . After 3 seconds, v f = 19.6 − ( 9.8 ) ( 3 ) = 19.6 − 29.4 = − 9.8 m s

The negative result tells us that the ball is on its way downward by this time (consistent with our choice of a negative value for the downward acceleration of gravity).