" 20 m/s² " means that if gravity is the ONLY force on the object (the object is in 'free fall'), then its speed increases by 20 m/s every second.
That's the answer to your question. Now, let me ask you another one:
How does a speedometer tied to a falling rock work ? How can it measure the rock's speed ?
Maybe one way would be to have a little tiny propeller on the front of the speedometer, and it could measure how fast the propeller is spinning as the rock falls through the air ? Great idea. But we already said the rock is in free-fall, so there's no air resistance, we can't have any air, and there's nothing to spin the propeller.
How would you do it ? How can you measure the rock's speed ?
'A ball is thrown straight up with an initial speed of 12 m/s_ What are the velocity and acceleration when it is at the top of its trajectory? Select all apply. v=12 mls a = 0 v =-12 mls a = 9.8 m/s2 Oa=-9.8 m/s2'
