CBSE ADDA

CBSE ADDA Temperature, Heat, and the Particle Theory           1.         What is a theory and can they be changed? A theory is an explanation based on all the available information.  A theory can be changed when new evidence is discovered. The Particle Theory 2.         According to the Particle Theory, what four characteristics are common to all matter? According to the Particle Theory: 1.  All matter is made up of tiny particle too small to see. 2.  These tiny particles are always moving 3.  The tiny particles have energy 4.  The more energy the particles have the faster they move 3.         Use the Particle Theory of Matter to explain why pollen grains move around when placed in a glass of water. Pollen grains move around in a glass of water because they are being pushed around by the invisi...

CBSE ADDA We have all noticed that when you heat something up, its temperature rises. Often we think that heat and temperature are the same thing. However, this is not the case. Heat and temperature are related to each other, but are different concepts. Heat is the total energy of molecular motion in a substance while temperature is a measure of the average energy of molecular motion in a substance. Heat energy depends on the speed of the particles, the number of particles (the size or mass), and the type of particles in an object. Temperature does not depend on the size or type of object. For example, the temperature of a small cup of water might be the same as the temperature of a large tub of water, but the tub of water has more heat because it has more water and thus more total thermal energy It is heat that will increase or decrease the temperature. If we add heat, the temperature will become higher. If we remove heat the temperature will become lower. Higher temperatures...

CBSE ADDA Current Electricity The term ‘current’ in general stands for the continuous flow of any material particles, e.g. water current means continuous flow of water particles through a pipe or a channel. Electric current in general means a continuous flow of electrons, ions or any electrically charged particles through a medium. In our everyday life, we are familiar with the electric current flowing through metallic conductors where flow of electrons only takes place. Positive charges can flow only through gases and nonmetallic solids and liquids. Units of electrical quantities I. Charge: The unit of charge in the S.I. system is coulomb. 2. Current strength: Current strength is often simply called current, its symbol is ‘I’ and the SI unit of it is ampere. Idea of resistance-its influence on regulating current The term "resist" means to oppose, so the property of opposing or resisting flow of electric charges in a conductor means resistance. The body resisting flow of ch...

CBSE ADDA Work, Power, Energy & Simple Machines Definition of work Work is said to be done if due to application of an external force on a body there is actual displacement of the body, except when the displacement is perpendicular to the direction of force. Work = Force x displacement of the point of application (body on which force is applied) in the direction of force. If W = work done, F = applied force, d = displacement of the point of application in the direction of force, then from the definition of work, W = F x d. Units of work In C.G.S. the unit of work is Erg. In M.K.S. it is Joule. 1 Joule = 107 Erg. Work done by a force If the point of application moves in the direction of applied force, work is done by the force. Work done against a force If a body has its displacement in the opposite direction of the applied force, work is done against the force. Power Rate of work done by an agent is known as its power. If w work is done by a body or a system in time t, then the p...

CBSE ADDA Newton's Laws of Motion (a) First Law: Everybody continues in its state of rest or of uniform motion in a straight line except in so far as it be compelled by any external impressed force to change that state. (b) Second law: The rate of change of momentum is directly proportional to the impressed force and takes place in the direction in which the force acts. (c) Third law: To every action there is an equal and opposite reaction. Inertia of Rest and Inertia of Motion Inertia of a body is its reluctance to change the state of rest or of uniform motion. It is also the degree of resistance a material body can offer to change of motion or rest condition. Inertia is of two types : (i) inertia of rest, (ii) inertia of motion. Inertia of rest Inertia of rest is the inherent property of a material body by virtue of which it continues in its state of rest until and unless no external unbalanced force compels it to move. Inertia of motion The tendency of a moving body to maintai...

CBSE ADDA Rest and motion An idea about frame of reference is necessary before discussion on rest and motion. Frame of reference While we observe a body that does not change its position with flow of time, we almost unknowingly refer to a second body which is nearby the first one. The second body should be a fixed one - it may be a domestic building or a tree, a lamppost or a prominent spot oh a road or a fixed star in the sky. This second body is called a reference body or a frame of reference. Definition Frame of reference is any nearby or a distant fixed object from which the distance and position of a body is observed as time elapses. Definitions of rest and motion Rest A body is said to be at rest if it does not change its position with time from a fixed neighboring object. Motion A body is in motion, if its position from a fixed neighboring object changes with time. Rest and motion are relative A body seems to be at rest with respect to one neighboring fixed object but the same...

CBSE ADDA Matter and Energy Mass Natural objects visible to us are made of different types of matter-solid, liquid or gas. The quantity of such matter that an object possesses is its mass. It is a physical quantity having magnitude only and no direction, so mass is a scalar quantity. Weight Every material particle on or near the earth is attracted towards the earth’s centre, called gravity. The weight of a body is the sum of all such pulls on all the particles the body is composed of. That is why a body composed of a larger number of particles i.e. a body of larger mass has greater weight than a body of smaller mass consisting of less number of particles. Force is the product of mass and acceleration, also, weight of a body is a force, so, weight of a body = mass of the body x acceleration due to gravity. Or, W = mg, where ‘W’ is the weight and ‘m’ is the mass of the body and ‘g’ is the acceleration due to gravity. Therefore, weight is a vector quantity because it has magnitude and d...

CBSE ADDA ‘Physics’- is the science which treats the general properties of the natural bodies or it can be described as the science of the material system. From the very advent of human brain on earth, physics is their true companion, an eternal associate. Now this subject, ‘physics’ became our most valuable guide to enhance our inner knowledge as well as to increase our outer comfort.

Nationalism In India Q. 15 .   Examine the Satyagraha movement organized by Gandhiji between 1916-18. Or With what major aims were the peasants movement organized in 1920? Ans. 1. Between 1916, he travelled to Champaran in Bihar to inspire the peasants to struggle against the oppressive plantation system. 2. In 1917, he took up the cause of the peasants of Kheda district of Ahmedabad to fight for reduction of revenue through Satyagraha Movement. 3. In 1918, Gandhiji organized Satyagraha Movement against cotton mill owners. 4. These movements were the first mass movements in Indian National Movement. These inculcated self confidence and a spirit to fight against injustice among people. Q .16 .  Why was the Khilafat Movement supported by Gandhiji in 1919? What was his main aim? Ans. In 1919, Gandhiji supported the Khilafat Movement to protest against the breakup of Ottoman (Turkish) empire by the British and humiliation caused to Turkish ...

Nationalism In India -1 Q. 9 .  Why is Dandi March Significant? Ans.  Dandi March is significant because it marked the beginning of the successful Civil Disobedience Movement involving masses from all parts of the country. Q. 10 .  Mention any four factors which were responsible in arousing the spirit of nationalism in India. Ans. 1. Political unification of the country under the Britishers. 2. Destruction of India’s old social and economic system. 3. Development of modern trade and industry. 4. The sense of being oppressed under colonialism provided a shared bond that tied many different groups. Q. 11.   Explain the new economic and political situations, created during the First World War in India. Ans . 1. The first world war led to a huge increase in defence expenditure which was financed by war loans and increasing taxes. 2. Custom duties were increased and income tax was introduced. 3. Between 1913-18 prices ...

10th History-Chapter 2   -  Nationalism In India Nationalism:  Patriotism; a feeling of collective belonging of one’s nation; sharing common feelings of identity. Nation-state: A state having common territory and inhabited by people sharing common language, race, culture, etc. Rowlatt Act:  An Act passed by British Government in India in 1919. It authorized the government to arrest and imprisons a person without trial. The Act was against civil rights. Civil disobedience: Refusal to comply with certain laws as a method of peaceful protest. Gudem Rebels:  The people who participated in the militant guerrilla movement in the Gudem hills of Andhra Pradesh. It was a resistance movement against the colonial government who prevented the people from entering the forests for grazing their cattle or collect firewood or fruits from the region. Q .1.  What was the notion of Swaraj for plantation workers in Assam? Ans.  For planta...

The Nationalist Movement in Indo-China-3 read here Q.12.   Explain the reasons for the popularity of ‘Go East Movement’. Ans.  In the first decade of 20th century ‘Go East Movement’ became popular. In 1907-08, some 300 Vietnamese students went to Japan to acquire modern education. Their primary objective was to drive out the French from Vietnam, overthrow the puppet emperor and reestablish the Nyuyen dynasty that had been deposed by the French. Since Japan had resisted colonization by European power and had a victory over Russia in 1907, the Vietnamese drew inspiration from them. They appeal the Japanese as fellow Asians for arms and to help in driving away the French. They established a branch of Restoration society in Tokyo. But Japanese ministry of interior clamped down the movement in 1908 and main leaders were deported. Q.13.   Explain the two different visions in opposing foreign domination in Vietnam. Ans.  Some in...

10th History chapter-1 Question Answer  The Nationalist Movement in Indo-China   part-1 Q. 6.  Mention the steps taken by the French to dismantle Chinese influence on Vietnam. Ans. 1. They established French school for the Vietnamese. They wanted to replace Chinese language in school either by French or by Vietnamese. 2. Some policy makers emphasized the use of French language as the medium of instruction. They felt that through this the Vietnamese would learn about French culture and civilization. 3. In 1907, Tonkin Free School was set up to provide western style education to spread French culture. 4. In religion the French introduced Christianity in Vietnam and gave challenge to Confucianism, the Chinese religion followed by many Vietnamese. Q. 7.   Why and how were the Vietnamese used in the rat hunt in 1902-03? Ans.  In 1903, the modern part of Hanoi was struck with bubonic plague. To prevent the invasion a rat hunt starte...

10th History Chapter 1 - The Nationalist Movement in Indo-China 1. Indo-China: The region in South East Asia comprising three countries –Laos, Cambodia and Vietnam. 2. Civilizing Mission: Mission or aim of civilizing the colonial people by introducing modern education and ideas in the colonies. On the pretext of civilizing, the imperial powers extended their control over colonies. 3. White-Collar jobs: Descriptive of workers mostly clerks who wear starched white collar. 4. Domino Effect: US believed that if Vietnam becomes a communist country it would have same effect on other neighbouring countries too and they would all become communist. The policy of Domino effect grew out of US fear for the spread of communism. Q. 1.  Why only one third of the students in Vietnam would pass the school leaving examination? Or Why most of students in the French schools failed to pass school-leaving examination? Ans.   Most of the students failed because the French fo...