Final answer:
To find the speed of the pebble on impact with the bottom of the well, you can use the formula speed = distance / time. By calculating the distance the pebble falls using the time it takes for the sound of the splash to return, you can then plug the values into the formula to find the speed. In this case, the speed of the pebble on impact is approximately 18.1 m/s.
Step-by-step explanation:
To find the speed of the pebble on impact with the bottom of the well, we can use the formula:
speed = distance / time
In this case, the distance is not provided, but we can calculate it by using the fact that the time it takes for the sound of the splash to return is equal to the time it takes for the pebble to fall. The formula to calculate the distance is:
distance = (1/2) * acceleration due to gravity * (time^2)
Plugging in the given values, we get:
distance = (1/2) * 9.8 m/s^2 * (3.8 s)^2 = 68.88 m
Now we can calculate the speed:
speed = distance / time = 68.88 m / 3.8 s = 18.1 m/s
Therefore, the speed of the pebble on impact with the bottom of the well is approximately 18.1 m/s.