Abdelmoghit Hintsches Pundit. What would happen when a bimetallic strip is cooled below room temperature? At normal room temperature , the two strips have the same length.
However, since brass expands or contracts more than iron when its temperature is raised or cooled , the bimetallic strip will bend one way or another depending on the temperature being above or below room temperature. Afrodisia Barmat Pundit. What happens when a metal bar is heated?
Metal expands when heated. Length, surface area and volume will increase with temperature. The degree of thermal expansion varies with different types of metal. Thermal expansion occurs because heat increases the vibrations of the atoms in the metal. Why does a bimetallic strip of brass and iron bend on heating? Here is your answer: A bimetallic strip is a strip of two metals bolted together.
It is used to check the expansion of metals. A bimetallic strip of brass and iron bends on heating because they expand and as one metal expands less than the other, it bends downwards. Mickey Lacuesta Pundit. Why does brass expand more than iron? In metals such as iron the forces between the atoms are stronger so it is more difficult for the atoms to move around. In brass the forces are a little weaker so the atoms are free to move about more. When the strip is heated the brass expands more than the iron so the strip beds.
Lourd Urro Teacher. What will happen if there is no thermostat to regulate the temperature in an electric iron? An electric iron is one of the most common appliances where a thermostat can be found… When this safety mechanism fails, dangerous overheating will occur that may eventually results into a catastrophic, and sometimes deadly fire….
The thermostat is set at gas but it is an electric furnace. Chakira Tolsada Supporter. How does a temperature sensor work? Problem Video Transcript a bi metallic strip comprises of two strips of different types of metals. Math Review - Intro In mathematics, a proof is a sequence of statements given to explain how a c…. Algebra - Example 1 In mathematics, algebra is one of the broad parts of mathematics, together w….
Why does a wire that carries electric current become hot? Why does an evaporating liquid cool down? Why does the ability…. Why does the partial pressure of water increase as temperature increases? How does temperature differ from heat? How does the electrical conductivity of a semiconductor change as the temper…. How does a thermocouple work as a temperature measurement device? Why does the temperature of melting ice not change even though energy is bei…. Share Question Copy Link. Report Question Typo in question.
Answer is wrong. See the diagram below. A bimetallic strip is made of two separate strips of metal stuck together. These two strips expand to a different extent when heated.
So, when the strip is heated, one strip will be longer than the other. Therefore, the bimetallic strip will bend. An example is iron and brass. Bimetallic strips are used in daily life for heat detection, such as that in fire alarms and thermostats. A thermostat is a small gadget used in various household appliances to automatically switch off the appliance when it is overheating.
In such applications, the bimetallic strip bends in order to complete or break a circuit. However, some work is required to recompress the gas Let's envision how this works. The compression stroke of the engine results from the fact that the engine is being used to put something in motion, for example a large wheel. As that wheel continues to turn because of its rotational inertia, it is able to drive the piston back inward and compress the gas.
Carnot's ideas derived from thoughts about how a water wheel works. Water at a high level drops and is caught by buckets in a wheel which rotates and does useful work. In principle, the water wheel could be made to run backwards as well. That is, by providing work to rotate the wheel in the opposite direction, water at the low level could be hoisted to water at the high level.
Hence, Carnot thought about a theoretical engine that would run both forward and backward, in analogy with the water wheel running forward and backward. Running forward, the heat engine would operate between a high temperature source and a low temperature environment. The engine does some useful work, but it also wastes some heat.
Running backward as a refrigerator, work is applied to extract heat from a region and exhausts it at a higher temperature. Carnot sought the most efficient possible engine that could operate in both directions. Keep in mind that we have been discussing and ideal engine. A real engine would waste even more energy since it would be impossible to control the heat and work so precisely.
In particular, moving parts would lose energy in the form of heat due to friction.
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