Select two metals that expand at very different levels; this disparity is what causes the bimetallic strip to move in the way it does. Two commonly used metals are brass and steel. Lay your two strips down on the work surface. When this bimetallic strip is heated, the brass expands more than the steel and the strip curves with the brass on the outside.
If the strip is cooled, it curves with the steel on the outside. Bimetallic strips are used as switches in thermostats. A bimetallic strip is used to convert a temperature change into mechanical displacement.
The strip consists of two strips of different metals which expand at different rates as they are heated. A bimetallic strip consists of two metal strips, one of iron and the other of brass, bolted together firmly. The two metals expand at different rate on heating. Brass expands more than iron on heating, thereby bending the bimetallic strip towards the iron strip. Thermal expansion is the tendency of matter to change in shape, area, and volume in response to a change in temperature.
All three states of matter solid, liquid and gas expand when heated. When a solid is heated, its atoms vibrate faster about their fixed points. Prolonged exposure to extreme heat can cause heat exhaustion, heat cramps, heat stroke, and death, as well as exacerbate preexisting chronic conditions, such as various respiratory, cerebral, and cardiovascular diseases.
Heat exhaustion, which is caused by too few fluids and long hours in high temperatures, causes heavy sweating, a fast and weak pulse and rapid breathing. Heat stroke, which is a life-threatening illness, happens when your temperatures rises above degrees Fahrenheit 41 degrees Celsius quickly — within minutes.
Begin typing your search term above and press enter to search. Since these are metals, it is sufficient that one of the two is a good enough conductor to be able to exploit this property in an electrical circuit. The bimetallic strip then becomes a switch that reacts depending on the temperature.
There are bimetallic strips in circuit breakers, fire alarms, blinking bulbs and thermostats. See also the eduMedia animation " bimetallic strip ". Enroll your school to take advantage of the sharing options.
Eventually, it bends so much that it breaks open the circuit. Definition: A bimetallic strip works on the principle of thermal expansion, which is defined as the change in volume of metal with the change in temperature.
The bimetallic strip works on two basic fundamentals of metals. The bimetallic strip constitutes one of the most trouble-free and durable thermometers.
It is simply two strips of different metals bonded together and held at one end. When heated, the two strips expand at different rates, resulting in a bending effect that is used to measure…. Thermometer and thermostat are examples of bimetallic tip devices. The coil changes the linear movement of the metal expansion into a circular movement due to the helicoidal shape it draws.
At extremely low temperatures, silicon and germanium expand with cooling rather than heating. The effect is called negative thermal expansion.
Steel has the same value as iron.
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