Non-standard Unit Measurement

Non-standard units are ordinary objects which are used because they are known to students and are readily available, for example, paces for length, books for area and cups for volume. Students should be provided with many opportunities to measure using these kinds of non-standard units. Non-standard units introduce the students to the use of units to provide numbers that describe a measure outcome, for example, the desk is 4 handspans across. Non-standard units introduce most of the principles associated with measurement:

• ·         Measures are expressed by counting the total number of units used.
• ·         During a measurement activity, the unit must not change.
• ·         Units of measure are not absolute but are chosen for appropriateness. For example, the length of the room could be measured by handspans but a pace is more appropriate.

Prior to introducing standard units, students need to realise that non-standard units tend to be personal and are not the most suitable for communication. For example, my hands are smaller than yours, so telling me to measure a piece of cloth three hands wide may not be useful.

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Standard Unit Measurement

No matter what field of science you enter, you will need to take measurements, understand them, communicate them to others, and be able to repeat them. In other words, we all have to speak the same basic language. Whether you are a chemist, a physicist, a biologist, an engineer, or even a medical doctor, you will need a consistent way of communicating size, mass, shape, temperature, time, amount, energy, power, and speed.

Consider the screen on which you're reading this text right now. It might be an LCD screen, in which case a very specific orientation of very specific molecules is aligned and realigned under very specific electric fields at precisely defined places on the screen. This alignment controls the way that light travels through the molecules. These alignments are generated by various computer algorithms but are universally accepted and defined to closely reproduce color, appearance, intensity, etc.

Though different in many ways, these various fields of science also have a great deal in common and it is all based on measurements. The chemist developing his or her specific formulation for a liquid crystal has to communicate meaningful information to an engineer about the physical properties required for manufacture and synthesis, and the engineer has to be able to communicate with other engineers, physicists, and chemists to design circuit boards, display screens, and electronic interfaces. If all don't speak the same language, the enterprise will never get off the ground.

The International System of Units is the metric system used in science, industry, and medicine and in much commerce worldwide . Depending on your age and geographic location, you might be very familiar with the "Imperial" system. Imperial units include gallons, feet, miles, and pounds, and the system remains in common use in many places for "everyday" measurements. In much of Europe, and in all scientific circles, however, the SI, or metric, system is in common use.

video standard unit measurement

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Characteristics living and non living things

Living Things

We are surrounded by living and non-living things. All animals and plants are living things and biology is the study of these living things. A cat playing with a ball is obviously living. A pigeon flying from tree to tree is also a living thing.

Sometimes it is not so easy to decide. Plants are living things but they do not play with balls or fly. If something is living it will carry out all of the seven activities shown opposite.

Some non-living things show one or two of the seven characteristics of living things. Machines, such as washing machines, can move. The car needs to be fed with petrol in order to move.

Crystals, such as ice crystals forming on a window, grow bigger if the conditions are right. For something to be living it has to show all of the seven characteristics of living things.

Non-living things

Sand, wood and glass are all non-living things. None of them shows any of the characteristics listed above. Non-living things can be divided into two groups. First, come those which were never part of a living thing, such as stone and gold.

The second group are those which were once part of living things. Coal is a good example. It was formed when trees died and sank into the soft ground. This happened many millions of years ago when the Earth was covered with forests. Paper is non-living but it is also made from trees. Jam is also non-living but it was made from the fruit of a plant.

The Seven Characteristics of Living Things

Feeding

All living organisms need to take substances from their environment to obtain energy, to grow and to stay healthy.

Movement

All living organisms show movement of one kind or another. All living organisms have internal movement, which means that they have the ability of moving substances from one part of their body to another. Some living organisms show external movement as well - they can move from place to place by walking, flying or swimming.

Breathing or Respiration

All living things exchange gases with their environment. Animals take in oxygen and breathe out carbon dioxide.

Excretion

Excretion is the removal of waste from the body. If this waste was allowed to remain in the body it could be poisonous. Humans produce a liquid waste called urine. We also excrete waste when we breathe out. All living things need to remove waste from their bodies.

Growth

When living things feed they gain energy. Some of this energy is used in growth. Living things become larger and more complicated as they grow.

Sensitivity

Living things react to changes around them. We react to touch, light, heat, cold and sound, as do other living things.

Reproduction

All living things produce young. Humans make babies, cats produce kittens and pigeons lay eggs. Plants also reproduce. Many make seeds which can germinate and grow into new plants.

video Characteristics living and non living things

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Measurements

A. UNDERSTANDING THE MEASUREMENT 

For example, you perform measurement activities long table with a pencil. In the event you compare the length of the table means the length of a pencil. The length of the pencil you use is as a unit. Something that can be measured and can be expressed with numbers called scale, whereas the comparison in a measurement called unit. Units used to perform measurements with the same results for everyone or fixed-called standard unit, while the unit is used to perform measurements with the same results for different people called non-standard units.

B. PRINCIPAL AMOUNT OF MAGNITUDE AND DERIVATIVES 

Understanding Physics Magnitude, Magnitude Cost, and Amount of Derivatives 

Inside our everyday conversation is the weight is the mass, whereas in the physics sense of weight and mass are different. Weight loss can be determined by using a weight scales. For example, after your weight weighed 50 kg or 50 kg mass in physics. Height or length and mass is something that we can measure and we can state with numbers and units. The length and mass of a physical quantity. Thus, the physical size of the physical quantities of an object is expressed in quantity. 
In addition there are also physical quantities quantities are not physical quantities, such as feeling sad, happy, and tired. Because feelings can not be measured and can not be expressed with numbers and units, then the feeling is not physical quantities.

Physical quantities are grouped into two, namely the principal amount and the amount of principal is the amount turunan.Besaran predefined in advance. Meanwhile, the amount of derivatives is a quantity that is derived from the basic quantities. 

System unit of physical quantities, in principle, be standard or standards, which are fixed, universal, and easy to use at any time by right. System standard units set in 1960 by scientists meeting in Sèvres, Paris. System of units used in education and knowledge is called the metric system, the metric system are grouped into large or MKS (Meter Kilogram Second) called the international system or abbreviated SI and metric systems of small or CGS (Centimeter Gram Second). 

Principal amount and the magnitude of the derivative along the unit can be seen in the following table.

In addition to the seven principal amount above, there are two additional principal amount, which is the corner of a flat field with units of radians (rad) and the corner of the room with the unit steradian (sr). 

Several tables and their derivatives Magnitude Its units

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