📔Important Scientific Laws,Principles and Theories👇

🔹 Ohm's Law - It states that the current passing through a conductor between two points is directly proportional to the potential difference across the two points provided the physical state and temperature etc. of the conductor does not change.

👍Pauli exclusion principle - It explains that no two electrons in the same atom or molecule can have the same set of quantum numbers.

🔹 Raman effect - It is the change in wavelength that occurs when light is scattered by the atoms or molecules in a transparent medium.

🔹 Tyndall effect - The scattering of light by very small particles suspended in a gas or liquid.

🔹 Boyles's Law - It states that temperature remaining constant, volume of a given mass of a gas varies inversely with the pressure of the gas. Thus,
PV = K (constant), where, P = Pressure and V = Volume.

🔹 Charles's Law - It states that pressure remaining constant, the volume of a given mass of gas increases or decreases by 1/273 part of its volume at 0 degree celsius for each degree celsius rise or fall of its temperature.

➔ Coulomb's Law - It states that force of attraction or repulsion between two charges is proportional to the amount of charge on both charges and inversely proportional to the square of the distance between them.

🔹 Heisenberg principle (uncertainty principle) - It is impossible to determine with accuracy both the position and the momentum of a particle such as electron simultaneously.

🔹 Archimede's principle - It states that a body when wholly or partially immersed in a liquid, experiences an upward thrust which is equal to the weight of the liquid displaced by it. Thus, the body appears to lose a part of its weight. This loss in weight is equal to the weight of the liquid displaced by the body.

🔹 Aufbau principle - It states that in an unexcited atom, electrons reside in the lowest energy orbitals available to them.

🔹 Avogadro's Law - It states that equal volumes of all gases under similar conditions of temperature and pressure contain equal number of molecules.

🔹 Brownian motion - It is a zigzag, irregular motion exhibited by small solid particles when suspended in a liquid or gas due to irregular bombardment by the liquid or gas molecules.

🔹 Bernoulli's principle - It states that as the speed of a moving fluid, liquid or gas, increases, the pressure within the fluid decreases. The aerodynamic lift on the wing of an aeroplane is also explained in part by this principle.

🔹 Gay-Lussac’s Law of combining volumes - Gases react together in volumes which bear simple whole number ratios to one another and also to the volumes of the products, if gaseous — all the volumes being measured under similar conditions of temperature and pressure.

👨🏿‍⚕Graham’s Law of Diffusion - It states that the rates of diffusion of gases are inversely proportional to the square roots of their densities under similar conditions of temperature and pressure.

🔹 Kepler's Law - Each planet revolves round the Sun in an elliptical orbit with the Sun at one focus. The straight line joining the Sun and the planet sweeps out equal areas in equal intervals. The squares of the orbital periods of planets are proportional to the cubes of their mean distance from the Sun.

🔹 Law of Floatation - For a body to float, the following conditions must be fulfilled: The weight of the body should be equal to the weight of the water displaced and the centre of gravity of the body and that of the liquid displaced should be in the same straight line.

🔹 Law of conservation of energy - It states that energy can neither be created nor destroyed but it can be transformed from one form to another. Since energy cannot be created or destroyed, the amount of energy present in the universe is always remain constant.

" የ12ኛ ክፍል መልቀቂያ ፈተና በተመረጡ ከተሞች በኦንላይን ይሰጣል " - ፕ/ር ብርሃኑ ነጋ

የ2016 ዓ.ም 12ኛ ክፍል መልቀቂያ ፈተና በተመረጡ ከተሞች በኦንላይን እንደሚሰጥ ትምህርት ሚኒስቴር አስታውቋል።

የትምህርት ሚኒስትሩ ፕ/ር ብርሃኑ ነጋ ፤ " ፈተናው ሙሉ በሙሉ በኦንላይን ለመስጠት ባይቻልም በክልሎች በተመረጡ ከተሞች ለመስጠት እየተሠራ ነው " ብለዋል።

በሁሉም ክልሎች ያሉ የተመረጡ ተማሪዎች በኦንላይን ፈተናቸውን ይወስዳሉ ሲሉም አሳውቀዋል።

ቀሪዎቹ ደግሞ በተለመደው አግባብ ፈተናቸውን እንደሚወስዱ ገልጸዋል።

የሀገር አቀፍ ምዘናና ፈተናዎች አገልግሎትም ፈተናው በኦንላይን ለመሥጠት የሚያስችል የቅድመ ዝግጅት ሥራ እየተሠራ ነው ብሏል።

ተማሪዎች በሙከራ ፈተና እንዲለማመዱ እንደሚደረግ ገልጿል።

የአሰልጣኞች ስልጠና በመሥጠት ተማሪዎች ተደጋጋሚ ስልጠና እንደሚሠጣቸው ተገልጿል።

ከቀጣይ ሳምንት ጀምሮ የአሰልጣኞች ስልጠና መስጠት ይጀመራል ተብሏል።
@hopetutorialprogram

via @tikvahethiopia

⭐️Common history concepts

✅ Ancient Civilizations: Mesopotamia, Ancient Egypt, Ancient Greece, and Ancient Rome.
 
✅ Feudalism: A system of social hierarchy prevalent in medieval Europe.

✅ Renaissance: A period of cultural, artistic, and intellectual rebirth in Europe.

🌟 Enlightenment: An intellectual movement emphasizing reason, science, and individual rights.

✅Industrial Revolution: Rapid industrial and technological advancement in 18th and 19th centuries.

🌟World Wars: Particularly World War I and World War II.

✅ Cold War: Ideological and geopolitical rivalry between the United States and the Soviet Union.

✅ Ancient Empires: Including the Persian Empire, Byzantine Empire, and Ottoman Empire.

✅ Napoleonic Era: The rise and fall of Napoleon Bonaparte in Europe.

✅Scientific Revolution: Transformation in scientific thought and discovery in the 16th and 17th centuries.

⭐️ Globalization: Increasing interconnectedness of the world's economies, cultures, and societies.
@ethioentrance600

Biology
1. In which geologic period is the evolution of humans most probably believed to have happened?
A. Tertiary period
B. Jurassic period
C. cretaceous
D. quaternary period
2. With a few weeks after heavy rains, pools become teemed with tadpoles. What is the source of the tadpoles?
A.The rain water
B. The mud on the floor
C. The decaying vegetation of the pond
D.The eggs laid by frogs
3. Which one of the following is a common idea held by all/the entire creationist?
A. Life is eternal
B. All life was created in six days
C. Life was created by supernatural being
D.Life come to earth from elsewhere in the universe
4. Lamarck’s theory of evolution is known as:
A. Natural selection
B. The survival of the fittest C.mutation theory
D. inheritance of acquired traits
5. Among the theories about the origin of life, which one better agrees with the concept of change in organisms and their genetic composition over generations being caused by meiosis, hybridization, natural selection or mutation?
A. Cosmozoan theory B. Bio chemical origin theory C. special creationism theory
D. spontaneous generation theory
6. Which of the following is the most accepted theory about the origin of life on earth?
A.Theory of spontaneous evolution.
B. The theory of chemical evolution
C.The cosmic theory
D. The theory of special creation
7. Which one of the following comes first in the course of organic evolution?
A.Photosynthesis organisms B.Free oxygen in the atmosphere 
C. land plant
D.multi cellular organisms
8. In which geologic period does the fossil record show more diverse and relatively higher forms of organisms?
A. Devonian B.. cretaceous C.. Jurassic D. Permian
9. From the time oxygen was first produced on the planet, it took approximately how many years for the levels to begin to rise?
A. 1,000,000 B. 10,000,000 C. 100,000,000
D. 1,000,000,000
10. The scientists who developed the theory of abiogenesis were:
A. Miller and Bernal
B.Miller and Oparin           C.Bernal and Haldane
D. Oparin and Haldane