The average force of a baseball is 18.9 N. Its mass is 0.145 kg.
Find the acceleration.

Work Shown:

Force = Mass*Acceleration

F = m*a

18.9 = 0.145*a

0.145*a = 18.9

a = 18.9/0.145

a = 130.344827586207

a = 130

I rounded to three sig figs because the given values are accurate to three sig figs. The units of acceleration are m/s^2.

Saying 130 m/s^2 means that every second, the baseball's velocity is increasing by 130 m/s. You can think of the velocities taking on multiples of 130 like so {130, 260, 390, 520, ...} though we're dealing with a continuous set of values rather than discrete set.

The acceleration is really large because the ball is going very fast in a short amount of time. For example, fast ball pitches can be 100 miles per hour, and the ball goes from 0 to 100 in a very short amount of time (less than 1 second).

365.25 earth days are in the year of a light year