It results change only in it's kinetic energy, it's KE will increase in accord with the work-energy theorem
Kinetic energy, KE, is modeled by the formula

, where m is the mass in kg and v is the velocity in m/s.
In this scenario, mass and one-half are constant but the velocity changes.
You can see that by squaring twice the velocity, that is equal to four times the original KE. Therefore, the answer is 4k.
Answer:
Balanced forces are equal and opposite forces that act on the same object. ... Action-reaction forces are equal and opposite forces that act on different objects, so they don't cancel out. In fact, they often result in motion.
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Answer:
we can say here that | v² - u² | is the same for upward as for downward and change in the speed is different here so | v - u | same whenever rock travel up, down for same time and not same distances
Explanation:
given data
base = 3.60 m
speed u = 8 m/s
height = 1.70 m
to find out
check change in speed
solution
we know here formula for v that is
v² = u² - 2gh ............1 for upward speed
v² = u² + 2gh ............2 for projected speed
so here put all value and find v with h = 3.60 - 1.70 = 1.9 m
v² = 8² - 2(9.8) 1.9 = 26.76
v² = 8² + 2(9.8) 1.9 = 101.24
v = 5.173 m/s ..............3
v = 10.061 m/s ...................4
so change in speed form 3 and 4 equation
change in speed = v - u = 8 - 5.173 = 2.827 m/s .................5
change in speed = v - u = 10.061 - 8 = 2.061 m/s ..................6
so now we can say here that | v² - u² | is the same for upward as for downward and change in the speed is different here so | v - u | same whenever rock travel up, down for same time and not same distances