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Name: Sada Joachim

Class: 4 Waldron

Teacher: Miss Burnette

Subject: Integrated Science

Due date: 01.May.2012


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I would like to express my special thanks of gratitude to my teacher Miss Burnette

as well as our principal Mrs Challenger who gave me the golden opportunity to do

this wonderful project on the topic temperature control, which also helped me in

doing a lot of Research and I came to know about so many new things. I am

really thankful to them. Secondly I would also like to thank my parents and

friends who helped me a lot in finishing this project within the limited time. I am

making this project not only for marks but to also increase my knowledge.

THANKS AGAIN TO ALL WHO HELPED ME.


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Acknowledgement

Introduction

Definition of temperature

Temperature measured

Types of thermometers

Features and principals of thermometers

Properties of liquid

Definition of humidity

Humidity measured

Effects of temperature and relative humidity on the body

Conclusion

Bibliography


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The term temperature control is used to describe the process

in which change of temperature of a space is measured or

otherwise detected, and the passage of heat energy into or out

of the space is adjusted to achieve a desired average

temperature.

This project is basically on temperature, what is, how it is

measured, the features and many more, just keep on reading I

know for a fact you will learn something new after today.


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Temperature is a measure of the average heat or thermal

energy of the particles in a substance. Since it is an average

measurement, it does not depend on the number of particles in

an object. In that sense it does not depend on the size of it.

For example, the temperature of a small cup of boiling water is

the same as the temperature of a large pot of boiling water.

Even if the large pot is much bigger than the cup and has

millions and millions more water molecules, it is still the same.

the pots of boiling water.

Temperature does not depend on the size or type of object.


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Many devices have been invented to accurately measure temperature. It all

started with the establishment of a temperature scale. This scale transformed the

measurement of temperature into meaningful numbers. In the early years of the

eighteenth century, Gabriel Fahrenheit created the Fahrenheit scale. He set the

freezing point of water at 32 degrees and the boiling point at 212 degrees. These

two points formed the anchors for his scale. Later in that century, around 1743,

Anders Celsius invented the Celsius scale. Using the same anchor points, he

determined the freezing temperature for water to be 0 degree and the boiling

temperature 100 degrees. The Celsius scale is known as a Universal System

Unit. It is used throughout science and in most countries. There is a limit to how

cold something can be. The Kelvin scale is designed to go to zero at this

minimum temperature.


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Alcohol Thermometer

Alcohol thermometer uses alcohol as the liquid to measure the temperature

variations. Alcohol expands when it absorbs temperature and contract in colder

temperatures. Most commonly used alcohol in these is ethanol, but different types

of alcohols can be used depending on the measured temperature and

environment in which the measurements are taken. The measurable temperature

range varies according to the used fluid inside the bulb. For example, boiling

point of ethanol is 80C and the freezing point is -115C. So in an alcohol

thermometer containing ethanol, -115C to 80C temperature variations can be

measured. Alcohol is a colourless, volatile fluid.

Mercury Thermometer

A small volume of silver colour mercury liquid is used inside the mercury

thermometer. Mercury is a highly toxic liquid; therefore, it should be handled with

care especially if the thermometer is broken. The freezing point of mercury is -

38.83 C and the boiling point is 357 C. Therefore, mercury thermometers are


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best at measuring higher temperatures than the lower temperatures. Thus, this is

widely used in laboratories to measure the temperature variations of chemical

reactions.

What is the difference between Alcohol Thermometer and Mercury

Thermometer?

Mercury thermometer has mercury inside the bulb as the temperature sensitive

fluid, and in alcohol thermometers, it is an alcohol.

Since alcohol is non-toxic, alcohol thermometers are much safer to use than

the mercury thermometers.

Alcohol thermometers can be used to measure very low temperatures. Since

mercury has a higher boiling point than alcohol, mercury thermometer can be

used to measure high temperatures.

Digital Thermometers

Digital thermometers use thermocouples or thermistors to sense the change in

temperature and display the temperature on a digital display. They are widely

used as clinical, outdoor and food thermometers. Infrared thermometers use the

infrared sensors to determine the temperature and have a digital display.

Outdoor ThermometersThe outdoor thermometers are used to measure the

temperature of the surrounding air. Wireless outdoor thermometers are very

popular these days.


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Food Thermometers

There are many food thermometers like the dial oven-safe thermometers, digital

instant thermometers, pop-up thermometers and disposable thermometers. The

dial oven-safe thermometers are used for thick foods and can be placed in the

food while you are cooking the food. However, the dial oven-safe thermometers

are not suitable for thin and watery foodstuffs. The digital instant thermometers

cannot be kept in the food while cooking. These thermometers read the

temperature within 10 seconds. The pop-up thermometers are used to measure

the temperatures of turkey and chicken. The disposable thermometer strips are

used to measure the temperature of food after they are cooked and they change

the colour according to the temperature. The colour of these thermometer strips

can be matched to a chart, which gives the corresponding temperature of food.

Celsius and Fahrenheit Thermometers

The Celsius thermometers use the Celsius (C) as the measurement unit and

Fahrenheit thermometers use Fahrenheit (F) as the temperature measurement

unit. Some thermometers have the measuring scales for both Celsius and

Fahrenheit. These thermometers give the reading in Celsius as well as

Fahrenheit.


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The thermometer has 5 basic parts which includes a scale, the bore, the bulb,

the steps and coloured alcohol known as mercury in the past.

The principals by which the work:

The scale of a thermometer: What is a thermometer scale? A thermometer scale

will give you a temperature reading of an object. Temperature is measured using

two different types of scales which include the Celsius scale and the Fahrenheit

scale. A thermometer scale will allow you to read the temperature in both the

Celsius degrees and the Fahrenheit degrees since most thermometers will consist

of both the Celsius scale and the Fahrenheit scale. Most countries use the

Celsius scale while the Fahrenheit scale is used in the USA.

The bore: the bore is the thin tube the goes through the centre of the whole

thermometer it is use as a passage way for the coloured alcohol/mercury.

The bulb: the bulb is a small chamber at the bottom for the thermometer which

house/contain the coloured alcohol/mercury.


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The coloured alcohol/mercury: is the liquid part of the thermometer which goes

up and down accord to the change in temper in otherto give the reading.


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It is able to stand tempers for 100 degrees Celsius and 0 degrees Celsius

without boiling of freezing, it is able to rise and drop accord to changes in

temperature.

It also has to be coloured, so you can read the etchings or markings properly,

and you can read the temperature.

The liquid also needs to be relatively cheap, so the factories can provide it and

make a profit.


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Humidity is a term for water vapour in the air, and can refer to any one of several

measurements of humidity. Formally, humid air is not "moist air" but a mixture of

water vapour and other constituents of air, and humidity is defined in terms of the

water content of this mixture, called the Absolute humidity. In everyday usage, it

commonly refers to relative humidity, expressed as a per cent in weather

forecasts and on household humidistats; it is so called because it measures the

current absolute humidity relative to the maximum. Specific humidity is a ratio of

the water vapour content of the mixture to the total air content. The water vapour

content of the mixture can be measured either as mass per volume or as a partial

pressure, depending on the usage.

In meteorology, relative humidity indicates the likelihood of precipitation, dew, or

fog. High relative humidity reduces the effectiveness of sweating in cooling the

body by reducing the rate of evaporation of moisture from the skin.


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There are various devices used to measure and regulate relative humidity. A

device used to measure relative humidity is called a psychrometer or hygrometer.

A humidistat is used to regulate the relative humidity of a building with a

dehumidifier. These can be analogous to a thermometer and thermostat for

temperature control.

Humidity is also measured on a global scale using remotely placed satellites.

These satellites are able to detect the concentration of water in the troposphere

at altitudes between 4 and 12 kilometres. Satellites that can measure water

vapour have sensors that are sensitive to infrared radiation. Water vapour

specifically absorbs and re-radiates radiation in this spectral band. Satellite water

vapour imagery plays an important role in monitoring climate conditions (like the

formation of thunderstorms) and in the development of future weather forecasts.

a hygrometer


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Humans are sensitive to humid air because the human body uses evaporative

cooling as the primary mechanism to regulate temperature. Under humid

conditions, the rate at which perspiration evaporates on the skin is lower than it

would be under arid conditions. Because humans perceive the rate of heat

transfer from the body rather than temperature itself, we feel warmer at a given

temperature when the relative humidity is high than when it is low.

For example, if the air temperature is 24 C (75 F) and the relative humidity is

zero per cent, then the air temperature feels like 21 C (69 F). If the relative

humidity is 100 per cent at the same air temperature, then it feels like 27 C (80

F). In other words, if the air is 24 C (75 F) and contains saturated water

vapour, then the human body cools itself at the same rate as it would if it were

27 C (80F) and dry.


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We all have use for a temperature control. It is for our own good, doing this

project I have learnt a lot and it taught me a little more about temperature and

humidity and the effect it can have on our bodies. You may not know it but we

use temperature control every day in everything that we do. So thanks for taking

your time and read my project I hope that u learnt a lot too.


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www.wikipedia.com/temperaturecontrol

www.wikipedia.com/humidity

www.answers.com

Macmillan cxc science series: Integrated science text book: Tania Chung-Harris

www.google.com/effectsofhumidityandtemperatureonthebody

Leon George: a pass high school student
http://www.wikipedia.com/temperaturecontrolhttp://www.wikipedia.com/temperaturecontrolhttp://www.wikipedia.com/humidityhttp://www.wikipedia.com/humidityhttp://www.answers.com/http://www.answers.com/http://www.google.com/effectsofhumidityandtemperatureonthebodyhttp://www.google.com/effectsofhumidityandtemperatureonthebodyhttp://www.google.com/effectsofhumidityandtemperatureonthebodyhttp://www.answers.com/http://www.wikipedia.com/humidityhttp://www.wikipedia.com/temperaturecontrol

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