Ahailstone traveling with a velocity of 43 meters per second comes to a virtual stop at 0.28 seconds after hitting water. what is the magnitude of it acceleration in water

Magnitude of acceleration = (change in speed) / (time for the change)

Change in speed = (final speed) minus (initial speed)

                               =  ( zero )          minus  (43 m/s) =  - 43 m/s .

Magnitude of acceleration = ( - 43 m/s ) / (0.28 sec)  =  - 153.6 m/s²

                                                                                  (about  - 15.7 G's)