An automatic weather station is set up on a hilltop to collect data. Measurement Sensor type Wind speed Rainfall Temperature Light level (a) Complete the ta...

(a) Suitable sensors for each measurement:

Each sensor is chosen because it can detect the specific physical quantity being measured. An anemometer typically uses rotating cups whose speed of rotation corresponds to wind speed. A thermistor changes its electrical resistance as temperature changes, providing a measurable signal.

(b) Two advantages of an automatic weather station over a human observer:

1. An automatic weather station can take readings continuously, 24 hours a day, without breaks or shifts. [1]
2. Sensors provide more precise and consistent numerical readings than human estimates, reducing measurement errors. [1]

(c) Output devices:

• Display: A monitor or screen to show real-time data readings and graphs of weather conditions. [1]
• Alert: A speaker, buzzer, or alarm to sound a warning when conditions such as high winds exceed a set threshold. [1]

(d) The sensors in the weather station produce analogue signals - these are continuously varying voltages that can take any value within a range. [1] The microprocessor can only process digital data (discrete binary values consisting of 0s and 1s), so an ADC is needed to convert the analogue sensor readings into digital form that the processor can work with. [1]

(e) The weather station could transmit data wirelessly using a radio transmitter, cellular (mobile) network module, or Wi-Fi to send readings at regular intervals to the central computer. [1] The central computer receives the data and stores it in a database for analysis, trend monitoring and weather forecasting. [1]