APPRECIATING THE IMPORTANCE OF STABILITY

Improving

1. When an object is tilted, it will start to topple over when the action line of its weight through its centre of gravity falls outside the base. This is as shown in the following diagram.

   


2. There are two ways to make an object more stable by lowering its centre of gravity which can be done either by reducing its height or attaching a heavy weight onto its base and increasing its base area.
3. In both ways, the action line of the weight through the centre of gravity falls within the base unless the object is tilted by a very large angle. The following diagram shows to improve the stability of a box.

Applying the principle of stability

1. Stability is very important to us. The use of unstable object would lead to accident. There will be great losses of property and lives if the object around us were to toppleover exactly.
2. There, the principle of stability is widely used in designing buildings, vehicles, furniture and appliances. They are designed to have a low centre of gravity and a larger base area for stability purposes.

• The buildings, houses, schools and factories are usually built on a heavy concrete foundation for stability. This lowers the centre of gravity of the building.

• A racing car is built low so that it has a low centre of gravity. Its tyre are wide and set apart to give the car a large base area.
• Lorries, trucks, buses and double-decker buses are designed with their heavy engines as near to the ground as possible to lower their centres of gravity.
• Furniture such as cupboards, tables and chairs are made more stable by having broad legs or legs that are set wide apart.
• The bottom of a glass is thicker and heavier to lower its centre of gravity.
• Many electrical appliances such as table lamps, standing fans and Bunsen burners are designed with a larger and heavy base.
• Laboratory apparatus such as tripod stands, conical flasks and measuring sylinders have a larger base area.
  

3. In fact, we also apply the principle of stability in many of aour daily activities.

• When arranging items in a tall shelf, we arrange the heavier items at th bottom shelves.
• An old person will bend forward and use a walking stick to make himself more stable while walking.
• Boxers and people who practice martial arts such as karate always stand with their feet wide apart and their body low when fighting.
• The passengers of double-decker bus are not allowed to stand on the upper deck so that the centre of gravity of the bus is not raised.