Final answer:
The stone's final velocity after free falling for 8 seconds is 78.4 m/s, and the height covered during this time is 313.6 meters.
Step-by-step explanation:
To calculate the stone’s velocity after it is in free fall for 8.0 seconds, we can use the equation of motion for an object under constant acceleration due to gravity:
Calculating Velocity
The equation to use is v = gt, where ‘v’ is the velocity, ‘g’ is the acceleration due to gravity (9.8 m/s²), and ‘t’ is the time in seconds. For complete 8 seconds of free fall, the stone's velocity (v) can be calculated as:
v = 9.8 m/s² * 8 s = 78.4 m/s
Calculating Height Covered
To calculate the height covered during this time, we can use the equation s = ut + ½gt², where ‘s’ is the distance, ‘u’ is the initial velocity (0 m/s since it starts at rest), and ‘t’ is the time. Therefore, the height covered is:
s = 0 m/s * 8 s + ½ * 9.8 m/s² * (8 s)² = ½ * 9.8 m/s² * 64 s² = 313.6 m