The magnitude of acceleration is (change in speed) / (time for the change).
Change in speed = (speed at the end) - (speed at the beginning) =
(16 m/s) - (0) = 16 m/s .
Time for the change = 4 s .
Magnitude of acceleration = (16 m/s) / (4 s) = 4 m/s per sec = 4 m/s² .
Answer:w=mxg
2x10 =20 N
Explanation:force acting downwards is mg mass into gravitional feild
The absence of external force in the outer space, allows the piece of rock to continue moving at the same velocity for thousands of years.
<h3>Absence of external force on the outer space</h3>
The outer space is almost an absolute vacuum, because it's nearly empty. There is no matter such as air in the outer space that will provide an external force needed to change the velocity of the piece of rock.
From Newton's first law of motion, an object in a state of rest or uniform motion in a straight line, will continue in that state unless it is acted upon by an external force.
Thus, the absence of external force in the outer space, allows the piece of rock to continue moving at the same velocity for thousands of years.
Learn more about outer space here: brainly.com/question/24701339
Power is equal to energy per unit time. In this case, power is proportional to energy while is inversely proportional to time,on the other hand. Given the two swimmers exerts same amount of energy but the faster swimmer just does things in faster time, then the faster swimmer should develop more power from shorter time