Hinge is a joint. It is designed to join two 'arms' together while letting them move freely. A lever is when a pivot, load, effort is present. Although hinge itself is not a lever, but taking our biceps as an example, that would be a Class 3 lever.
Physical properties. Tungsten is a hard brittle solid whose color ranges from steel-gray to nearly white. Its melting point is the highest of any metal, 3,410Â°C (6,170Â°F) and its boiling point is about 5,900Â°C (10,600Â°F). Its density is about 19.3 grams per cubic centimeter. Tungsten conducts electrical current very well.
Tungsten and its alloys are widely used for filaments in older style (not energy saving) electric bulbs and electronic tubes. It is used for making heavy metal alloys because of its hardness. Tungsten is used for high-temperature applications such as welding. High speed steel (which can cut material at higher speeds than carbon steel), contains up to 18% tungsten. Tungsten carbide (WC or W 2 C) is extremely hard and is used to make drills.