To find the average speed of the ball, we need to consider the entire trip, which includes both the upward and downward motions.
When the ball is thrown vertically upward, it moves against gravity, gradually slowing down until it reaches its highest point and starts coming back down. The time it takes for the ball to reach its highest point is the same as the time it takes for the ball to fall back down to its starting point (assuming no air resistance).
The time it takes for the ball to reach its highest point can be found using the equation:
time = velocity / acceleration
In this case, the initial velocity (upward) is 19.6 m/s, and the acceleration due to gravity is approximately 9.8 m/s² (assuming no air resistance). Plugging these values into the equation, we have:
time = 19.6 m/s / 9.8 m/s² = 2 seconds
Since the time it takes to reach the highest point is 2 seconds, the total time for the complete trip (up and down) is 2 seconds + 2 seconds = 4 seconds.
Now, to find the average speed, we use the formula:
average speed = total distance / total time
The total distance traveled is zero because the ball starts and ends at the same position. Therefore, the average speed of the ball for its complete trip is:
average speed = 0 meters / 4 seconds = 0 m/s
So, the average speed of the ball is 0 m/s.