Question
Solar Pool Heater
A pool owner is building a solar heater to keep her pool a comfortable 85°F. So far, she has a design that consists of piece of wood with black drip irrigation tubing coiled around and secured. This part of the design is shown in the picture.

The pool owner is making a few choices in the design of the solar heater. She is deciding whether to leave the wood plain or paint it, either white or black. She wants to choose the option that will help the solar heater warm the pool quickest. To make her decision, she cuts three pieces of wood that are one foot by one foot. Then, she paints one of them white and one of them black. She leaves the third piece of wood its original color. She places the three pieces of wood into the sunlight for 30 minutes and records their temperatures every five minutes. The table shows this data.
Wood Color Temperatures (in °F)0 minutes5 minutes10 minutes15 minutes20 minutes30 minutesPlain Wood757576767777White Paint757575757676Black Paint757678808182
The second decision the pool owner would like to make is whether she should use 100 feet of drip irrigation tubing or 200 feet of drip irrigation tubing. She would also like to connect the design to a small programming device that will turn the water pump for the pool on and off based on the pool's temperature. When the pump is on, water will be pumped out of the pool and through the black tubing. Then, the water will flow back into the pool as it exits the tubing. When the pump is off, no water will be pumped out of the pool and through the black tubing. The pool owner needs to decide how to program the device so that the temperature of the pool is as close to 85°F as possible.
Two-Part Question
Multiple Choice Question
The following question has two parts. First, answer Part A. Then, answer Part B.
Part A:
After the pool owner finalizes her design, she runs the solar heater. The graph shows the data she collects during a 24-hour period.

Use the data to identify how the design has failed.
A.
The solar heater causes the pool to heat up to above average temperatures at night.
B.
The solar heater causes the pool to cool down below average temperatures at night.
C.
The solar heater causes the pool to heat up to above average temperatures during the day.
D.
The solar heater causes the pool to cool down below average temperatures during the day.
Multiple Choice Question
Part B:
How could the design be updated to address this failure of the design?
A.
The solar heater can be programmed to stay off at night.
B.
The solar heater can be programmed to stay on at night.
C.
The solar heater can have longer tubing to cool the pool more during the day.
D.
The solar heater can have longer tubing to warm the pool more during the day.
Answers
GPT-4o mini
Part A:
Based on the information you've provided and the patterns associated with solar heating, the correct choice is likely:
**B. The solar heater causes the pool to cool down below average temperatures at night.**
This indicates that the design allows the pool to lose heat overnight, as solar heaters typically rely on sunlight to warm the water, and without input from the sun during the night, temperatures can drop.
Part B:
To address the failure identified in Part A, the best option would be:
**A. The solar heater can be programmed to stay off at night.**
By programming the heater to remain off during the night, the pool owner would prevent further cooling at night when there is no solar input. This could help maintain a more consistent temperature throughout the night. However, note that this does not directly prevent cooling; the option might aim to minimize the impact of the heater running during a period of lower temperatures.
Based on the information you've provided and the patterns associated with solar heating, the correct choice is likely:
**B. The solar heater causes the pool to cool down below average temperatures at night.**
This indicates that the design allows the pool to lose heat overnight, as solar heaters typically rely on sunlight to warm the water, and without input from the sun during the night, temperatures can drop.
Part B:
To address the failure identified in Part A, the best option would be:
**A. The solar heater can be programmed to stay off at night.**
By programming the heater to remain off during the night, the pool owner would prevent further cooling at night when there is no solar input. This could help maintain a more consistent temperature throughout the night. However, note that this does not directly prevent cooling; the option might aim to minimize the impact of the heater running during a period of lower temperatures.