We have seen that most of the solids will expand when heated and shrink when cooled, when a railway station is installed, a small room should be made between the rail connection to allow the rail it expands during the summer. Rivets are used to connect parts of the steel frame building is a good example about effect cooling on the solid object. Initiated by heating the rivet nail, and then plugged in when it it's hot. When it is cool, rivets it will shrink and pull the two sections of steel tightly.
Expansion is expressed in terms of substance in one, two, or three dimensions. In this case we are talking about expansion of solids in length (one dimension), area (two dimensions), and volume (three dimensions). Especially on the linear expansion is important to note. Once we know the value, we can easily determine the expansion area and its contents,
We can measure the length of expansion, in terms of linear expansion coefficient, is the change in length of a unit length of material for each unit change in temperature. These coefficients have been measured with great accuracy for most of the solids. For example, if the temperature of a particular piece of steel with a length of 1 degree Celsius increase, the length of the steel was increased by a factor 0.000011. Similarly, pieces of steel will be reduced in length by the same factor when the temperature dropped 1 degree Celsius, so if a bar of steel 10 feet in length, in a temperature range from 0 degrees to 35 degrees centigrade in a year, will expand and shrink within a 10x0 , 000011x35 = 0.00385 meters or About 4 millimeters a year. It is important to note that, besides depending on temperature changes, major expansion is also dependent on the length of the steel.
Because the expansion coefficient of each metal is different, the metal will expand more than other metals when subjected to the same heat level, an interesting picture about unequal expansion of this alloy is the metal bar. This alloy consists of two metal rods of different types such as copper and iron are riveted or welded into a single trunk. If we heat a rod of this sort, which one metal will expand more than others so the rod would be bent or circular
Rods of metal alloys used for various purposes. Bimetallic thermometer which we generally see on the shelves of the kitchen, made of metal alloys in the form of a spiral, it is composed of copper rod in the inner and outer spiral was steel, copper has a much higher coefficient of expansion than steel. When heated, these rods tend to be straightened and this will cause the pointer attached to it moves over a scale. Rods of metal alloys are widely used as a thermostat for controlling temperature.
Sometimes the expansion of solids due to heating produces a startling effect. Is well known that the glassware will crack if subjected to temperature changes suddenly. For example, if we pour hot oil into a cold bottle. This is because the cup or the glass is a poor conductor of heat in other words, heat is transferred slowly into the glass. The sides of the cup is thus heated unevenly, thus expanding the different speeds. Tension ensued and because cup is a brittle material, the cup will break. Glassware called pireks are long cooling process called annealing, that produce a low coefficient of expansion. Thus, this type of cup has small possibility to broken when temperature change suddenly
In general, the liquid expands much larger than solids when heated. Liquid will release an enormous pressures when hindered its expansion, for example, with limited in a container. In the case of liquid water, we are better measured in cubic expansion than in the linear range. Cubic expansion coefficient is in units of volume expansion at 0 degrees Celsius to 1 degree Celsius temperature rise rather than a specific liquid.
As with other liquids, water expands when heated and shrink when cooled to a temperature above 4 degrees Celsius. However, at temperatures between 0 degrees Celsius to 4 degrees Celsius, the water expands when cooled and shrinks when heated. This means water at a temperature of 4 degrees centigrade will expand and become lighter as well as cooled or heated.
Expansion is expressed in terms of substance in one, two, or three dimensions. In this case we are talking about expansion of solids in length (one dimension), area (two dimensions), and volume (three dimensions). Especially on the linear expansion is important to note. Once we know the value, we can easily determine the expansion area and its contents,
We can measure the length of expansion, in terms of linear expansion coefficient, is the change in length of a unit length of material for each unit change in temperature. These coefficients have been measured with great accuracy for most of the solids. For example, if the temperature of a particular piece of steel with a length of 1 degree Celsius increase, the length of the steel was increased by a factor 0.000011. Similarly, pieces of steel will be reduced in length by the same factor when the temperature dropped 1 degree Celsius, so if a bar of steel 10 feet in length, in a temperature range from 0 degrees to 35 degrees centigrade in a year, will expand and shrink within a 10x0 , 000011x35 = 0.00385 meters or About 4 millimeters a year. It is important to note that, besides depending on temperature changes, major expansion is also dependent on the length of the steel.
Because the expansion coefficient of each metal is different, the metal will expand more than other metals when subjected to the same heat level, an interesting picture about unequal expansion of this alloy is the metal bar. This alloy consists of two metal rods of different types such as copper and iron are riveted or welded into a single trunk. If we heat a rod of this sort, which one metal will expand more than others so the rod would be bent or circular
Rods of metal alloys used for various purposes. Bimetallic thermometer which we generally see on the shelves of the kitchen, made of metal alloys in the form of a spiral, it is composed of copper rod in the inner and outer spiral was steel, copper has a much higher coefficient of expansion than steel. When heated, these rods tend to be straightened and this will cause the pointer attached to it moves over a scale. Rods of metal alloys are widely used as a thermostat for controlling temperature.
Sometimes the expansion of solids due to heating produces a startling effect. Is well known that the glassware will crack if subjected to temperature changes suddenly. For example, if we pour hot oil into a cold bottle. This is because the cup or the glass is a poor conductor of heat in other words, heat is transferred slowly into the glass. The sides of the cup is thus heated unevenly, thus expanding the different speeds. Tension ensued and because cup is a brittle material, the cup will break. Glassware called pireks are long cooling process called annealing, that produce a low coefficient of expansion. Thus, this type of cup has small possibility to broken when temperature change suddenly
In general, the liquid expands much larger than solids when heated. Liquid will release an enormous pressures when hindered its expansion, for example, with limited in a container. In the case of liquid water, we are better measured in cubic expansion than in the linear range. Cubic expansion coefficient is in units of volume expansion at 0 degrees Celsius to 1 degree Celsius temperature rise rather than a specific liquid.
As with other liquids, water expands when heated and shrink when cooled to a temperature above 4 degrees Celsius. However, at temperatures between 0 degrees Celsius to 4 degrees Celsius, the water expands when cooled and shrinks when heated. This means water at a temperature of 4 degrees centigrade will expand and become lighter as well as cooled or heated.
0 comments:
Post a Comment