The answer is <span>D- a motorcycle with a constant velocity.
Velocity is much more stable in terms of speed and distance that can be associated with the dynamics of equilibrium (balance) compared to speed alone. It brings the constant relationship between the two elements.
Speed is only focused on time of travel and not with direction. While acceleration does not show equilibrium but only a change in speed.
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The average speed is 52km
The time needed for the hammer to reach the surface of the Earth is 3.54 s.
<h3>
Time of motion of the hammer</h3>
The time of motion is calculated as follows;
t = √(2h/g)
where;
- h is height of fall
- g is acceleration due to gravity
t = √(2 x 10 / 1.6)
t = 3.54 s
Thus, the time needed for the hammer to reach the surface of the Earth is 3.54 s.
Learn more about time of motion here: brainly.com/question/2364404
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