As this happens over twelve seconds, you would take the total difference in velocities and divide it by twelve to find the change per second
44.0 m/s - 2.0 m/s = 42.0 m/s
42.0 m/s / 12 s = 3.5 m/s2
the acceleration of the rock would be 3.5 m/s2
C. It transfer energy as heat to the surrounding air. This answer is incorrectly
Answer:3.4 seconds
Explanation:
Initial velocity(u)=0
acceleration=34.5m/s^2
Height(h)=200m
Time =t
h=u x t - (gxt^2)/2
200=0xt+(34.5xt^2)/2
200=34.5t^2/2
Cross multiply
200x2=34.5t^2
400=34.5t^2
Divide both sides by 34.5
400/34.5=34.5t^2/34.5
11.59=t^2
t^2=11.59
Take them square root of both sides
t=√(11.59)
t=3.4 seconds