To find the average rate of change of the dolphin's position over the total time of 12.5 seconds, we can follow these steps:
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Determine the initial and final positions:
- The highest point above the water is +3.5 meters (above the surface).
- The lowest point below the water is -10 meters (below the surface).
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Calculate the change in position:
- The change in position (\(\Delta y\)) from the highest point to the lowest point can be calculated as: \[ \Delta y = \text{final position} - \text{initial position} = -10 , \text{m} - 3.5 , \text{m} = -13.5 , \text{m} \]
- This result indicates that the dolphin moved 13.5 meters downward (since it's a negative change in position).
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Determine the time taken:
- The time (\(\Delta t\)) taken for this movement is 12.5 seconds.
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Calculate the average rate of change:
- The average rate of change (\(v_{avg}\)) of the dolphin's position can be found using the formula: \[ v_{avg} = \frac{\Delta y}{\Delta t} \]
- Plugging in the values: \[ v_{avg} = \frac{-13.5 , \text{m}}{12.5 , \text{s}} = -1.08 , \text{m/s} \]
Interpretation: The average rate of change of the dolphin's position over the time interval of 12.5 seconds is approximately -1.08 meters per second. The negative sign indicates that the average movement is downward, meaning the dolphin was descending into the water during this time period.