Answer:
Time, I believe. Pretty sure it's time lol
Answer:
Explanation:
Although there is absolutely NO regard for significant digits, I can help you with this, nonetheless.
The equation for Potential Energy is PE = mgh. We have everything but the height of the ball. We have to solve for that using a one-dimensional motion equation:
v² = v₀² + 2aΔx, where Δx is our displacement (the height we need for PE). Filling in and keeping in mind that at the max height of parabolic travel, the final velocity of the object is 0:
0 = (21.5)² + 2(-9.8)Δx and
0 = 462.25 - 19.6Δx and
-462.25 = -19.6Δx so
Δx = 23.58 m. Using this as the h in our PE equation:
PE = .19(9.8)(23.58) so
PE = 43.9 J, choice C.
5 second fall starting at 0 m/s
ball strikes ground at a speed = 49 meters per second.
Use the distance swan and the time elapsed in that interval.
Average velocity = distance / time
Average velocity = [4.0 m + 3.0m] / 3.2 s = 2.1875 m/s
