Tuesday 22 March 2011

Introduction and History


INTRODUCTION OF LIQUID

  • Liquid is one of the three primary states of matter, with the others being solid and gas. A liquid is a fluid. Unlike a solid, the molecules in a liquid have a much greater freedom to move. The forces that bind the molecules together in a solid are only temporary in a liquid, allowing a liquid to flow while a solid remains rigid.
    A liquid, like a gas, displays the properties of a fluid. A liquid can flow, assume the shape of a container, and, if placed in a sealed container, will distribute applied pressure evenly to every surface in the container. Unlike a gas, a liquid may not always mix readily with another liquid, will not always fill every space in the container, forming its own surface, and will not compress significantly, except under extremely high pressures. These properties make a liquid suitable for applications such as hydraulics.
    Liquid particles are bound firmly but not rigidly. They are able to move around one another freely, resulting in a limited degree of particle mobility. As the temperature increases, the increased vibrations of the molecules causes distances between the molecules to increase. When a liquid reaches its boiling point, the cohesive forces that bind the molecules closely together break, and the liquid changes to its gaseous state (unless superheating occurs). If the temperature is decreased, the distances between the molecules become smaller. When the liquid reaches its freezing point the molecules will usually lock into a very specific order, called crystallizing, and the bonds between them become more rigid, changing the liquid into its solid state (unless supercooling occurs).

    HISTORY OF LIQUID

    • Liquid is one of the three classical states of matter. Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly constant density. A distinctive property of the liquid state is surface tension, leading to wetting phenomena.

      The density of a liquid is usually close to that of a solid, and much higher than in a gas. Therefore, liquid and solid are both termed condensed matter. On the other hand, as liquids and gases share the ability to flow, they are both called fluids.




INTRODUCTION OF VOLUME 
Volume is how much three-dimensional space a substance (solid, liquid, gas, or plasma) or shape occupies or contains,[1] often quantified numerically using the SI derived unit, the cubic metre. The volume of a container is generally understood to be the capacity of the container, i. e. the amount of fluid (gas or liquid) that the container could hold, rather than the amount of space the container itself displaces.
Three dimensional mathematical shapes are also assigned volumes. Volumes of some simple shapes, such as regular, straight-edged, and circular shapes can be easily calculated using arithmetic formulas. The volumes of more complicated shapes can be calculated by integral calculus if a formula exists for the shape's boundary. One-dimensional figures (such as lines) and two-dimensional shapes (such as squares) are assigned zero volume in the three-dimensional space.
The volume of a solid (whether regularly or irregularly shaped) can be determined by fluid displacement. Displacement of liquid can also be used to determine the volume of a gas. The combined volume of two substances is usually greater than the volume of one of the substances. However, sometimes one substance dissolves in the other and the combined volume is not additive.[2]
In differential geometry, volume is expressed by means of the volume form, and is an important global Riemannian invariant. In thermodynamics, volume is a fundamental parameter, and is a conjugate variable to pressure.

HISTORY OF VOLUME

Quantities of liquids are commonly measured in units of volume. These include the SI unit cubic metre (m3) and its divisions, in particular the cubic decimetre, more commonly called thelitre (1 dm3 = 1 L = 0.001 m3), and the cubic centimetre, also called millilitre (1 cm3 = 1 mL = 0.001 L = 10−6 m3).
The volume of a quantity of liquid is fixed by its temperature and pressure. Liquids generally expand when heated, and contract when cooled. Water between 0 °C and 4 °C is a notable exception. Liquids have little compressibility: water, for example, requires a pressure of the order of 200 bar to increase its density by 1/1000. In the study of fluid dynamics, liquids are often treated as incompressible.


1. Introduction to volume of liquid.
2. Understand and use the vocabulary related to volume of liquid.
3. Measuring and comparing volumes of liquid.
4. Measure and compare volumes of liquid by direct comparison and by using uniform non-  standard units.
5. Measure and compare volumes of liquid using standard unit.

Learning outcomes for topic Volume of liquid are:
1. Use the vocabulary related to volume in practical contexts 

2.Compare the volumes of two liquids by direct comparison.

3. Measure volumes of liquid using standard unit. 

4. Two teaching aids and two teaching activities.


CONCLUSION
The volume of an object is the amount of space it takes up. The Ancient Greek genius Archimedes realized he could measure the volume of any shape solid by submerging it in a full container of water and then measuring the volume of the water that spilled over.

The development of modern teaching techniques has revolutionized the schooling system. The teaching activity is no more restricted to the delivery of boring facts. It has changed into a lively and inspiring means of mutual communication. The essentials of classroom management skills include audio- visual aids and all sorts of other teaching materials. To enhance an effective interaction and to achieve the curriculum objectives teachers are always on the lookout for suitable aids and materials. 
HISTORY

Hogshead

Generally, a hogshead is an old time standard of measurement in the form of a large wooden cask of liquid or some other food product.
The measurement is exclusively a certain volume, standardized by the British Weights and Measures act of 1824. It was used most widely for alcoholic beverages.
It's about sixty-three gallons of liquid in U.S. measurements. Those of us who are Cajun may remember that historically, a hogshead was used in Louisiana to measure sugar and cotton in Colonial days.



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