Question

A watch with a liquid crystal display (LCD) does not function properly when it is exposed to low temperatures during a trip to Antarctica. Explain why the LCD might not function well at low temperature.

Short answer

The functionality of an LCD watch is compromised at low temperatures, such as in Antarctica, due to the effect of these conditions on liquid crystal molecules. At low temperatures, the molecules have a slower response time and may even enter a solid-like phase, which hinders their ability to control light passage and display an image. As a result, the poor screen refresh rates and image quality make the LCD watch less effective or even non-functional.

Step-by-step solution

Understanding Liquid Crystal Displays (LCDs)

Liquid crystal displays (LCDs) work by using liquid crystal molecules that respond to electric fields. These molecules have a twisted structure in their natural state, allowing them to control the passage of light. When an electric field is applied, the liquid crystal molecules untwist, blocking the passage of light. This process enables the LCD screen to display an image.

Liquid Crystal Behavior at Low Temperatures

When a liquid crystal is exposed to low temperatures, its molecules may exhibit slower response times and limited ability to change their orientation in response to an electric field. Additionally, at very low temperatures, liquid crystals may change phase from liquid-like to solid-like which drastically alters their properties. In this solid-like phase, the liquid crystal would lose its ability to control the passage of light effectively.

Impact of Low Temperatures on LCD Functionality

In low temperatures, the slower response time of the liquid crystal molecules in an LCD can lead to poor screen refresh rates and image quality. Moreover, if the liquid crystals enter a solid-like phase due to the low temperature, they would not be able to control light effectively, and the LCD screen would be rendered non-functional.

Conclusion

The reason a watch with an LCD might not function well at low temperatures, such as during a trip to Antarctica, is due to the impact of low temperatures on the properties and behavior of the liquid crystal molecules. Low temperatures can slow down the response time of liquid crystal molecules and may cause them to enter a solid-like phase, impairing the ability of the LCD screen to control the passage of light and display an image.