A factory uses sensors to monitor conditions during the manufacturing of chocolate. (a) Identify three types of sensor that could be used in the chocolate f...

(a) Three types of sensor suitable for a chocolate factory: [6]

1. Temperature sensor: measures the temperature of the chocolate during heating, tempering, and cooling stages. [1] This is essential because chocolate must be processed at precise temperatures to achieve the correct texture and consistency. If the temperature is too high, the chocolate burns and becomes bitter; if too low, it does not melt or temper properly. [1]
2. Moisture/humidity sensor: measures the level of moisture in the air or in ingredients during production. [1] Controlling humidity is critical because excess moisture can cause the chocolate to become grainy, develop a white "bloom" on its surface, or fail to set properly, all of which reduce product quality. [1]
3. Pressure sensor: measures the pressure in the moulding or extrusion equipment during production. [1] Correct pressure ensures that the right amount of chocolate is dispensed into each mould, producing consistent portion sizes and preventing overfilling or underfilling. [1]

(b) Sensors are preferred over human workers for monitoring factory conditions for two reasons: [2]

1. Sensors can take readings continuously, 24 hours a day, without breaks, fatigue, or lapses in attention. This ensures that conditions are monitored at every moment during production. [1]
2. Sensors provide more accurate and consistent measurements than human observation. A temperature sensor can detect changes of a fraction of a degree, whereas a human worker would rely on less precise estimation, increasing the risk of errors. [1]