Answer:
The speed (magnitude of the velocity) is 14.4 m/s
Step-by-step explanation:
Vertical Launch Upwards
It occurs when an object is launched vertically up without taking into consideration any kind of friction with the air.
If vo is the initial speed and g is the acceleration of gravity, the speed vf at any time is calculated by:

A tennis ball is launched vertically up with an initial speed of vo=34 m/s. At time t=2 s, its speed is:



The speed (magnitude of the velocity) is 14.4 m/s