35. Thay đổi thông số hóa lý

Nguyên tắc con

1. Change the physical state of the object (solid, liquid, gas)
2. Change its concentration or viscosity
3. Change its degree of flexibility
4. Change its temperature

Ví dụ

• Liquid soap instead of a bar
• Gas liquefied for storage
• A suspension whose stiffness varies with conditions

Ứng dụng theo lĩnh vực

• electronics: Cooling a chip in a thin device would need a large heat sink. Liquid in a sealed thin tube that boils near the chip and condenses at the far end moves a lot of heat in little space.
• materials: Liquid glue runs and needs time to dry. A glue that is solid at room temperature is heated to melt, flows in like a liquid, and sets as soon as it cools.
• mechanical: A rigid robot finger crushes soft objects, and a soft one drops heavy ones. A finger whose stiffness is set by the air pressure inside can grip both.
• medical: An injected drug must be thin to pass the needle but should stay put inside the body to act longer. A formulation that thickens at body temperature flows during injection and stays where it was placed.