2 years ago

You throw a ball straight up at 45 m/s. how many seconds elapse before it is traveling downward at 9 m/s?

1 answer:

8 0

In order to change from 45 m/s up to 9 m/s down, the velocity
of the ball has to change by (45+9)= 54 m/s downward.

Gravity adds 9.8 m/s of downward speed to any falling object
every second.

So the change takes (54/9.8) = 5.5 seconds .

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