person would like to install a device in his house which turns a light on when the pressure is between 0.75 and 1 atmospheres (ATM), and sounds a warning signal when the outside pressure is 0.75 ATM or below. The light and the sound will never go off simultaneously. Write a solution to this problem.
The correct answer and explanation is :
To solve the problem of controlling a light and a warning signal based on atmospheric pressure, we need to design a system that performs two tasks:
- Turn on the light when the atmospheric pressure is between 0.75 and 1 ATM.
- Sound the warning signal when the atmospheric pressure is 0.75 ATM or lower.
- Ensure that the light and the warning signal never turn on at the same time.
Solution Approach
The problem can be solved using a pressure sensor that measures the atmospheric pressure. The sensor’s readings will be used to control the light and warning signal. We will use simple conditional logic to handle the transitions between the light and the warning signal.
Step-by-step Process:
- Sensor Input: The system will use a pressure sensor that continuously monitors the atmospheric pressure.
- Pressure Conditions:
- If the pressure is between 0.75 and 1.0 ATM (inclusive), turn the light on.
- If the pressure is 0.75 ATM or lower, activate the warning signal.
- Exclusive Operation: To ensure the light and the warning signal never turn on simultaneously, we can use a mutual exclusion logic:
- If the light is on (pressure between 0.75 and 1.0 ATM), the warning signal is off.
- If the pressure is 0.75 ATM or lower, the warning signal is activated and the light is turned off.
Detailed Algorithm:
- Pressure Reading:
- Measure the current atmospheric pressure.
- If pressure is between 0.75 and 1.0 ATM, turn on the light and turn off the warning signal.
- If pressure is below or equal to 0.75 ATM, turn off the light and activate the warning signal.
This system ensures that:
- When the pressure is within the safe range (between 0.75 and 1.0 ATM), the light is illuminated.
- When the pressure drops to 0.75 ATM or below, the light goes off and the warning signal is triggered to alert about the low-pressure situation.
Hardware Requirements:
- Pressure Sensor: To detect the atmospheric pressure.
- Relay/Control Module: To switch the light and warning signal based on the pressure reading.
- Microcontroller (e.g., Arduino/Raspberry Pi): To handle the logic for turning the light and the warning signal on and off.
Conclusion:
This system uses simple logic to ensure that the light and warning signal never conflict, providing a clear, intuitive solution for monitoring atmospheric pressure.