43 Teachers to be feted for exemplary work

The Teachers Service Commission, TSC, is set to reward 43 teachers for exemplary performance and long service. The teachers, most of whom, have been examiners for a period of more than 20 years will, apart from receiving promotions from the employer, have their names presented to the President, HE Uhuru Kenyatta, for further recognition and awards. These revelations were made by TSC Chief Executive Officer, Dr. Nancy Macharia, during the releasing exercise of this year’s Kenya Certificate of Secondary Education, KCSE, results on Friday.
“This year, I wish to recognize these forty (teachers) who have consistently rendered exemplary services as examiners for twenty years and above. Over the years they have risen to the positions of either chief examiners or assistant chief examiners. The TSC will be recognizing them in line with the Commission’s policy on recognition and award. And, in addition, we shall also be forwarding their names to his excellency the President (Uhuru Kenyatta) to confer them with awards and honours,” Said Dr. Macharia.
The teachers to be feted are:
Jane Wangui G
Marion Kithinji
Gikonyo GM
Oyuga B. Asioya
Barasa W. Enos
Gitabari J. Njagi
Mugoh N. Simon
Muhindi J. K
Muluka S. Nzilu
Matu W. Grace
Mohammed A. Ali
Omoro Moses
Kipyegon S. Benard
Muchwanju O. Moses
Ngahu K. Benjamin
Vincent Mulure
Nyaanga Zachary
Christopher Kulei
Motanya Isaac
Mutambo K. Albert
Eunice M. Mashaka
Nyariki R. Orina
Said O. Hinga
Khamis M. Omar
Kezia Ochieng
Chege Agnes Wangui
Catherine K. Mavyala
Denis K. Ibala
Gabriel K. Kinyoho
Kiruga S. Nduta

How to receive KCSE 2018 examination results online or via SMS

1. Visit the KNEC schools’ portal by clicking on: https://www.knec-portal.ac.ke/. This will take you to the KNEC schools’ portal home page.

2. Under the ‘SECONDARY SCHOOLS (KCSE)’ tab, click on Performance analysis link.

3. In the next window, indicated as; KCSE- PERFORMANCE ANALYSIS, enter the User name and password as used during the registration process. Now log into the portal and the results will be displayed there in terms of mean grade summary and Aggregate point Summary.

4. To download the results, click on the export icon on the window and select your preferred format i.e PDF, word, excel….

The results will download automatically, once you select the format.

How to receive the results via SMS

1. Go to Compose New SMS in your phone.

2. Type your full KCSE 2018 index Number.

3. Send the SMS to 20076.

Please send the SMS once the results have been announced. Each SMS costs KShs. 25

MODERN PHYSICS (theories of relativity and quantum physics)

Physicists often refer to the theories of relativity and quantum physics as “modern physics,” to distinguish them from the theories of Newtonian mechanics and Maxwellian electromagnetism, which are lumped together as “classical physics.” As the years go by, the word “modern” seems less and less appropriate for theories whose foundations were laid down in the opening years of the 20th century. After all, Einstein published his paper on the photoelectric effect and his first paper on special relativity in 1905, Bohr published his quantum model of the hydrogen atom in 1913, and Schrödinger published his matter wave equation in 1926. Nevertheless, the label of “modern physics” hangs on.

All in all, two lines of investigation are truly “modern”, but at the same time have the most ancient of roots. They center around two deceptively simple questions:
What is the universe made of?
How did the universe come to be the way it is?
Progress in answering these questions has been rapid in the last few decades. Many new insights are based on experiments carried out with large particle accelerators. However, as they bang particles together at higher and higher energies using larger and larger accelerators, physicists come to realize that no conceivable Earth-bound accelerator that can generate particles with energies great enough to test the ultimate theories of physics. There has been only one source of particles with these energies, and that was the universe itself within the first millisecond of its existence.

In the 1930s, there were many scientists who thought that the problem of the ultimate structure of matter was well on the way to being solved. The atom could be understood in terms of only three particles—the electron, the proton, and the neutron. Quantum physics accounted well for the structure of the atom and for radioactive alpha decay.
The euphoria did not last. By the end of that same decade, there was discoveries of a host of new terms and a veritable flood of particles (such as muon, pion, kaon, and sigma), names that you should not try to remember. All the new particles are unstable; that is, they spontaneously transform into other types of particles according to the same functions of time that apply to unstable nuclei.

If you are temporarily bewildered, you are sharing the bewilderment of the physicists who lived through these developments and who at times saw nothing but increasing complexity with little hope of understanding. If you stick with it, however, you will come to share the excitement physicists felt as marvelous new accelerators poured out new results, as the theorists put forth ideas each more daring than the last, and as clarity finally sprang from obscurity.

The main message of this piece of writing is that, although we know a lot about the physics of the world, grand mysteries remain.

Rules & guidelines for The Kenya Science and Engineering Fair

Eligibility

Participants must be school going students from registered Kenyan schools
Each student participating must be less than 20 years by the time National Science Fair is held
At National and Regional Fairs participants must only register in one project.
Participants can either be an individual or a team of two students
Team entries will not substitute members in a given year or change to individual participation. Likewise, individual entry cannot be changed to team entry
The same project cannot be submitted twice in different years without any progress since its first presentation. Any modification/progress must be pointed out in the new application.
Participants at the National level must have participated in all the other levels

Guidelines/Requirements & Rules

Researchers must avoid any scientific misconduct or fraud, such as falsifying data or records, and piracy or plagiarism (presenting the work of another researcher as one’s own)
Each participant must sign a plagiarism form.
All competitors and mentors must communicate in English only
Before presentations, the Scientific Review Committee (SRC) must review and approve all projects.
KSEF encourages the development of entrepreneurial projects, which may lead to the marketing of these products. Participants are advised to obtain legal advice about patent applications before entering their work at any KSEF. Once a design or product has been on public display, it can NOT be patented. However, if a project is displayed for judges only, no patent rights should be lost.
The final application requires you to submit a double-spaced research paper typed using font 12, with a maximum of 20 pages that include:

• An abstract (less than 250 words).
• An Introduction/ background information (with a summary of literature)
• A section stating the objective of the project.
• A section on methods used to achieve the objective
• A results and discussion section
• A conclusion and
• References

Any research or experiment on potentially hazardous biological agents, animal or human subjects must be done under the supervision of a qualified scientist/mentor. Unless with a signed letter from the qualified a scientist/mentor, the following are NOT allowed in KSEF

• Living organisms including animals, fish, insects and plants
• Agar plates and other growth mediums for microbiology studies
• Human or animal parts including tissues and body fluids (for example blood, urine, hooves, skins etc)
• Flammable substances
• Dangerous chemicals: Poisons, drugs, medications, controlled substances, hazardous substances and devices (for example firearms, weapons, ammunition, reloading devices, knives and any other sharp instruments)
• Photographs or other visual presentation depicting humans or vertebrate animals in surgical techniques, dissections, necropsies or other lab procedures or who belittle people in any way or show animals being harmed in any way
• Brand names or any other branded products
• Food substances that are not in completely sealed containers (plastic wrap is not acceptable as it can easily be removed).
• Water except if in sealed apparatus
• Any apparatus deemed unsafe by the KSEF organizers.

Students must keep a research book as they conduct their research and the same should be brought to KSEF competitions.
Students are advised to bring multiple copies of their final abstract to be distributed to curious scientists.
Students MUST have display boards / booths at the National and Regional fairs.
Students should come with pre-printed materials to prepare their posters.
No cell phones are allowed to students. The judges should not make or receive phones judging
The dress code for students:
No miniskirts are allowed
Formal (school uniform) must be worn always

DISPLAY REGULATIONS


The following regulations must be adhered to when participants exhibit their project
Maximum Size of Display

Depth (from front to back) = 30 in or 76 cm

Width (from side to side) = 48 in or 122 cm

Height (from floor to top) = 108 in or 274 cm

Fair provided tables will not exceed 36 in or 91 cm

Maximum project size includes all project materials and supports. If you are using a table, it becomes part of the project.

What the Display Board Contains

PROJECT CATEGORIES

S/No.	Category	Details
1	Mathematical Science	Algebra, Analysis, Applied mathematics, Geometry, Probability and Statistics, Others
2	Physics	Astronomy, Atoms, Molecules, Solids, Instrumentation and Electronics, Magnetics and Electromagnetism, Particle physics, Optics, Lasers, Theoretical physics.
3	Computer Science	Algorithms, Data Bases, Artificial intelligence, Networking and communications, Computational science, Graphics, Computer systems, OS, Programming, Software engineering.
4	Chemistry	Analytical chemistry, General chemistry, Inorganic chemistry, Organic chemistry & Physical chemistry.
5	Biology and Biotechnology	Cellular Biology, Molecular genetics, Immunology, Antibiotics, Antimicrobials, Bacteriology, Virology, Medicine and health sciences.
6	Energy and transportation	Aerospace and, Alternative fuels, Fossil fuel energy, Renewable energies.
7	Environmental science and management	Bioremediation, Ecosystems management, Environmental engineering, Land resource management, Recycling, Waste management, Pollution.
8	Agriculture	Agriculture / Agronomy Development, Photosynthesis, plant physiology, plant systematic, plant evolution, Animal Sciences (Animal Husbandry).
9	Food technology and Home Economics	Development of food products, Design of processes, Food engineering, Food microbiology, Food packing, Food preservation, Food safety.
10	Engineering	Design, building, use of engines, machines and structures, apparatus, manufacturing processes, Aeronautical Engineering, Vehicle development.
11	Technology and applied technology	Appropriate technology, innovations in science, industry, Knowledge economy & research development.
12	Robotics
13	Behavioral science	Stress management,

You may also want to read Overview Of The Kenya Science and Engineering Fair

You may also want to read Nyamira kenya science and engineering fair workshop 2019

The Kenya Science and Engineering Fair

HISTORICAL BACKGROUND OF THE SCIENCE AND ENGINEERING FAIR

The Kenya Science and Engineering Fair (Formerly, National Students’ Congress on Science and Technology) was launched in 1962 by the science teachers who were members of the then Kenya Science Teachers Association (KSTA). In its initial stages, the congress only catered for secondary schools around Nairobi. It was not until 1965 that the congress acquired a national outlook by allowing schools in the republic to participate. Entries from students were restricted to Physics, Chemistry and Biology.  In 1989, the range of entries to the congress was expanded to accommodate the subjects offered in 8-4-4 curriculum.

Until 1995, the venue of the congress was restricted to Kenya Science Teachers College.  However, it was found necessary that the activity be reorganized in line with the Ministry of Education policy governing all the co-curriculum activities and it was resolved that the venue for hosting the event be made rotational.                                

In line with the implementation of the country new constitution, the Ministry of Education in 2012,grouped the counties into regions to replace the provinces which were abolished. The regions were as follows.

1. Metropolitan (Nairobi, Machakos, Makueni and Kajiado Counties)
2. Aberdares (Kiambu, Kirinyaga, Muranga, Nyeri, Nyandarua and Laikipia Counties)
3. Highlands (Marsabit, Isiolo, Meru, Tharaka Nithi, Embu, Kitui and Samburu Counties)
4. Mau (Nakuru, Narok, Kericho, Bomet, Baringo, Elgeyo Marakwet, Uasin Gishu and Nandi Counties)
5. Nzoia (Kakamega, Busia, Vihiga, Bungoma, Trans Nzoia, West Pokot and Turkana Counties)
6. Lake (Kisumu, Siaya, Homa Bay, Migori, Kisii and Nyamira Counties)
7. Coastal (Mombasa, Kwale, Kilifi, Lamu, Tana River and Taita Taveta Counties)
8. Northern (Garrissa, Wajir and Mandera Counties)

However, the naming of these regions changed as from the year 2017 to the names that were there before 2012. These includes; Nairobi region( 1 county), Eastern region( 8 counties), Western region( 4 counties), Central region ( 5 counties), Coast (6 counties) , Rift valley ( 14 counties) North Eastern ( 3 counties), and  Nyanza region (6 counties)

The KSEF has re-organized the fair both in terms of categories and mode of presentation in line with international standards. There are 11 categories for competition which include; Agriculture, Biology, Chemistry, ICT, Food Technology, Mathematics, Physics, Environmental Science, Technology, Engineering and Energy. They are soon thinking of including an extra category of social and behavioral sciences.

Also, the fair has been affiliated to Intel International Science and Engineering Fair (Intel ISEF) which is always held in U.S.A in the month of May and ESKOM Expo for young scientists held in October in Johannesburg, South Africa. Four teams participated this year in the Intel ISEF competition at Los Angeles, USA. These were from SCLP Samaj School, while two schools –  Stephen kositany Girls and St. Stephen Sikusi Boys secondary schools participated in South Africa International Science Fair.

 This year, six projects will be selected to represent the country in these fairs in October this year and in May next year.
You may also want to read Rules & guidelines for The Kenya Science and Engineering Fair

Topic six - Thermal expansion

TEMPERATURE is the degree of hotness or coldness of a body

Temperature of a body is measured by an instrument called a thermometer.

Temperature is a basic physical quantity and is measured in degrees celcious (⁰C) or Kelvin (K).

The S.I unit of temperature is Kelvin (K) which is a scalar quantity.

THERMAL EXPANSION AND CONTRACTION OF SOLIDS, LIQUIDS AND GASES

All substances increase in size when heated. This increase in size of a substance is called expansion. On the other hand when a substance is cooled it decreases in size. This decrease in size is called contraction.

EXPANSION IN SOLIDS

Thermal expansion and contraction in solids can be demonstrated using a ball and ring experiment. Set the apparatus as shown below.

NOTE: The ball should pass through the ring when both are at room temperature

·        Heat the ball and try to pass it through the ring. Observe what happens.

·        Leave it for sometime

OBSERVATION

·        When both the ball and the ring are at the same room temperature, the ball just passes through the ring.

·        When the ball is heated, it does not go through the ring but when left there for sometime, it goes through.

EXPLANATION

·        When heated, the ball expands so that it cannot go through the ring. When left on the ring for some time, the temperature of the ball decreases and it contracts.

·        At the same time, the temperature of the ring increases and it expands so that the ball goes through.

WHY SOLIDS EXPANDS ON HEATING

The molecules of a solid are closely packed together and are continuously vibrating in their fixed positions

When a solid is heated the molecules gain more kinetic energy and therefore make larger vibrations about their fixed positions. This increase in vibration means that the molecules collide with each other with larger forces and the molecules increases and so the solid expand.

LINEAR EXPANSIVITY

The measure of the tendency of a particular material to expand is called its expansivity e.g. aluminium expands more than iron thus aluminium has higher expansivity than iron.

material	Linear exapnsivity (K-1) x 10-6
Aluminium	26
Brass	19
Copper	16.8
Iron	12
Concrete	11
Steel	11
Glass	9

The knowledge of linear expansivity values is applied in the designing of materials to ensure that they are able to operate well under varying thermal conditions.

Ordinary glass expands at a higher rate than Pyrex glass. When hot water is poured into a tumbler made of glass it breaks but does break in Pyrex glass.

Concrete and steel are reinforced together because they are of the same linear expansivity. Hence cannot crack under varying thermal conditions.

The bimetallic strip

When two metals of different linear expansivity are riveted together they form a bimetallic strip.

Brass and iron are used to make bimetallic strip as shown below.

On heating the bimetallic strip, brass expands more than iron. The brass thus becomes longer than the iron for the same temperature range. Hence, the bimetallic strip bends with brass on the outside of the curve as shown in (b) below

On cooling, the brass contracts more than iron. It therefore becomes shorter than the iron and thus ends up being on the inner side of the curve as shown in (c) above

APPLICATIONS OF EXPANSION AND CONTRACTION IN SOLIDS

   1.  RAILWAY LINES

Gaps are left between the rails. Expansion for the rail is provided by overlapping the plane ends using overlapping joints as shown in the figure below

If these gaps for the expansion are not provided then during hot weather, they rails may buckle out, bend and cause derailment of the train leading to destruction and accidents.

1 2.  STEAM PIPES

Pipes carrying steam from boilers are fitted with loops or expansion joints to allow pipes to expand and contract easily when steam passes through and when it cools down.

1 3. TELEPHONE WIRES

 They are loosely fixed to allow for contraction and expansion. During cold weather, they contract and when it is warm they expand.

Telephone or electricity wires appear to be shorter and taut in the morning. However in hot afternoons, the wires appear longer and slackened.

2 4. STEEL BRIDGES

In bridges made of steel girders, one end is fixed and the other end placed on rollers to allow for expansion as shown

   5.  RIVETS

Thick metal plates, sheets and girders in ships are joined together by means of rivets.

The rivet is fitted when hot and then hammered flat. On cooling, it contracts, pulling the two firmly together as shown

1 6.  ELECTRIC THERMOSTAT

A thermostat is used to maintain a steady temperature in some devices such as electric iron box, refrigerators, fire alarm and flashing unit for indicator lamp in motor cars.

EXPANSION AND CONTRACTION IN LIQUIDS

The experimental set up below can be used to demonstrate expansion of a liquid.

                                                        Heat

A glass flask is filled with coloured water and heated as shown above

OBSERVATION

Immediately the level of coloured water on the tube drops slightly at first and then starts rising.

EXPLANATION

The initial fall of the level of the water is due to the expansion of the glass flask which gets heated first. The water starts expanding when heat finally reaches it and it rises up the tube.

NOTE: The water expands faster than the glass.

QUESTION

Explain why there is a drop in the level of the water initially followed by a steady rise in the level of water.

Different liquids expand more than others for a given temperature as shown in the diagram

In this case, methylated spirit expands most, followed by alcohol and finally water.

EXPANSION IN GASES

The experiment below can be used to demonstrate expansion of air.

Invert the flask with glass tube dipped into the water as shown.

Warm the flask with your hands for some time and note what happens.

Remove your hand and let the flask cool while the tube is still inserted in water.

OBSERVATION AND EXPLANATION

When the flask is warmed the level of water column inside the glass tube drops indicating air expands. When the flask is warmed further, some bubbles are seen at the end of the glass tube.

On cooling the air inside the flask contracts and water rises up the glass tube.

THE ANOMALOUS (UNUSUAL) EXPANSION OF WATER

Solids, liquids and gases expands when heated and contracts when cooled. Water however shows an anomalous (unusual) behaviour in that it contracts when it is temperature is raised from 0^oC to about 4^oc.

When ice is heated from say -20^oC, it expands until its temperature reaches 0^oC and it melts with no change in temperature. The melting is accompanied by contraction. The water formed will still contract as its temperature rises from 0^oC as shown

Above 4⁰C, the water expands with increase in temperature. Since volume of a given mass of water is minimum at 4^oC, water at this temperature has a maximum density, slightly higher than 1g/cm³.

A sketch of the variation of density with temperature

At the melting point of water (o⁰C) there is a drastic increase in the volume, resulting in a large decrease in density as the ice forms.

EFFECTS OF ANAMALOUS EXPANSION OF WATER.

1 1. Freezing of lakes and ponds

Water in lakes and ponds usually freezes in winter. Ice is less dense than water and floats on water.

Since ice a bad conductor of heat it insulates the water below against heat losses to the cold air above.

Water remains at 4⁰C being the most dense, remains at the bottom of a lake while ice being less dense floats on layers of water at different temperatures as shown.

Fish and other aquatic animals and plants can therefore survive by living in the liquid layers below the ice.

1 2. Icebergs

Since the density of ice (0.92g/cm³) is slightly less than that of water it floats with only a small portion above the water surface. The rest and bigger portion rests under water. A big mass of such submerged ice is known as an iceberg.

It poses a great danger to ships as navigators cannot see the submerged part.

2 3. Weathering of Rocks

When water in a crack in a rock freezes, it expands. This expansion breaks the rock into small pieces.

3 4. Water pipes

Water pipes bursts when the water flowing through the pipes freezes

MEASURING TEMPERATURE

THERMOMETER

A thermometer is an instrument used for measuring temperature. There are various types of thermometers in use.

The common types of thermometer include;

•  Liquid-in-glass thermometer.
•   Clinical thermometer
•  Six’s maximum and minimum thermometer

LIQUID-IN-GLASS THERMOMETER

A liquid-in-glass thermometer commonly in use is mercury or coloured alcohol as the thermometric substance.

The volume of the liquid changes uniformly with the change in temperature.

The liquid in the bulb must; (characteristics)

•        Be easily seen (visible).
•       Expand or contract uniformly and by a large amount over a small range of temperature.
•   Not stick to the inside of the tube. (Should not wet the inside of the tube.
•   Have a wide range of temperature.

THERMOMETRIC LIQUIDS-the most common in use is mercury and alcohol.

Mercury freezes at -39^oC and boils at 357^oC while alcohol freezes at -115^oC and boils at 78^oC. Alcohol is therefore suitable for measuring temperatures below -39^oC.

PROPERTIES OF THE TWO THERMOMETRIC LIQUIDS

Alcohol	Mercury
Low boiling point, 78oC	High boiling point, 357oC
Low melting point, -115oC	Relatively higher melting point, -39oC
Poor thermal conductor	Good thermal conductor
Expansion slightly irregular	Expands regularly
Wets glass	Does not wet glass
Coloured to make it visible	Opaque and silvery

QUESTION

Explain why water is not used as a thermometric liquid?

TEMPERATURE SCALE

A scale of temperature is obtained by selecting two temperatures known as fixed points

The range between this two fixed points is divided into a number of equal divisions.

On the celcious scale, the lower fixed point is the temperature of pure melting ice and is taken as 0^oC. The impurities in the ice would lower its melting point.

The upper fixed point is the temperature of steam above water boiling at normal atmospheric pressure of 760mmHg and is taken as 100^oC.

The temperature of boiling water itself is not used because any impurities in water would raise its boiling point. The temperature of steam is not affected by impurities in water.

When these points have been marked, the range between them is divided into 100 equal divisions. Each division is called degree.

FEATURES OF A COMMON THERMOMETER

The basic features of a common laboratory are as shown below.

Bulb- Carries the liquid in the thermometer. It has a thin glass wall for effective heat transmission between the liquid and body whose temperature is taken.

Capillary bore – Liquid expands and contracts along the capillary tube. It is narrow for high degree of accuracy.

Glass stem –Is a thick wall surrounding the capillary bore. It also serves as a magnifying glass for easy reading of scale.

CELCIOUS AND KELVIN SCALE

They are the commonly used temperature scale.

The celcious scale has the fixed points at 0^oC and 100^oC.

In Kelvin scale, the temperature of pure melting ice is 273K while that of pure boiling water at normal atmospheric pressure is 373K.

The lowest temperature in the Kelvin scale (0K) is referred as absolute zero. This is the temperature at which the energy of the particles in material is zero.

To change ^oC to Kelvin

T = (ѳ – 273) K              where ѳ is the temperature in ^oC

Example

 Convert 25^oC in Kelvin

T = (25 + 273)

     = 298 K

To change Kelvin to ^oC

Ѳ = (T- 273) ⁰C              where T is the temperature in Kelvin

Example

Convert 1 K

Ѳ = 1-273

    =-272^oC

NOTE: Temperature in Kelvin scale cannot have a negative value because the absolute zero, (0 K), is the lowest temperature attainable.

CLINICAL THERMOMETER

A clinical thermometer is an instrument used to measure the temperature of a human body.             

It uses mercury as its thermometric substance and has a narrow constriction in the tube just above the bulb.

The diagram below shows the main features of a clinical thermometer.

The constrictionprevents the mercury level from falling down when it contacts with the human body.

The clinical thermometer has a short scale of temperature from 35^oC to 43^oC spread over its entire level. This is because the human body temperature falls slightly above or below 37^oC which is the temperature of a normal and healthy person.

SIX’S MAXIMUM AND MINIMUM THERMOMETER

This thermometer is used to record the maximum and minimum temperature of a place during a day.

The thermometer consists of a U-tube connected to two bulbs. The U-tube contains mercury.

The two bulbs contain alcohol.

The figure below shows the main features of a six’s maximum and minimum thermometer.

Working of the thermometer

When temperature raises alcohol occupying volume of bulb A expand and forces mercury in the U-tube to rise on the right hand side.

The mercury in turn pushes the steel index A upwards. The maximum temperature can be noted from the lower end of the steel index A.

On the other hand when the temperature falls, alcohol in the bulb A contracts and the mercury is pulled back rising u the left hand side of the U-tube. The index B is then pushed up. During contraction of the alcohol, index A is left behind ( in the alcohol) by the falling mercury.

The minimum temperature is then read from the lower end of index B.

NOTE: To reset the thermometer, a magnet is used to return the steel indices to the mercury surfaces.

The bimetallic thermometer