CLASS: IX :: Gravitation
CLASS: IX NCERT (CBSE) Gravitation SUMMARY Freely falling object: Is the object which moves towards the Earth due to force of gravity Acceleration due to gravity: It is the acceleration produced in an object due to force of gravity Acceleration due to gravity varies from place to place Acceleration due to gravity is zero at the centre of the Earth Acceleration...
CLASS: IX :: Force and Laws of Motion
CLASS: IX NCERT (CBSE) Force and Laws of Motion SUMMARY If an object does not change its position with respect to time and the surroundings, it is said to be at rest, else it is said to be in motion. Force is that which changes or tries to change the state of rest or of motion of an object by a...
CLASS: IX :: Motion
CLASS: IX NCERT (CBSE) Motion Summary • Motion: Whenever a body changes its position continuously with respect to the position of other bodies around it then it is said to be in motion • Rest: An object which does not change its position with respect to its surroundings is said to be at rest • Distance: It is the actual length of the path...
CLASS: IX :: Diversity in Living Organisms
CLASS: IX NCERT (CBSE) Diversity in Living Organisms SUMMARY Aristotle, the Greek philosopher, classified animals based on whether they live on land, in water or in the air. Classification of living organisms is based on characteristics and divided the animals into groups and sub-groups. Charles Darwin put forward the idea of evolution in 1859, in his book, The Origin of Species. ...
CLASS: IX :: Tissues
CLASS: IX NCERT (CBSE) Tissues SUMMARY 1) A group of cells, that are similar in structure and work together to achieve a particular function, forms a tissue. 2) Types of plant tissues include meristematic and permanent tissues. 3) Meristematic tissues are rapidly dividing tissues. 4) Apical meristem is present at the apical or growing tips of stems and roots. 5) Lateral meristem is present in the...
CLASS: IX :: The Fundamental unit of Life
CLASS: IX NCERT (CBSE) The Fundamental unit of Life SUMMARY All living organisms are made of cells. Marcello Malpighi, proposed that plants are made of tiny structural units called 'Utricles'. Robert Hooke observed many tiny, hollow, room- like structures in a thin slice of cork through a compound microscope and called them cells. Leeuwenhoek, in 1674, with the improved microscope, discovered...
CLASS: IX :: Structure of the Atom
CLASS: IX NCERT (CBSE) Structure of the Atom Summary • Atom is the smallest particle of an element, which maintains its identity throughout chemical and physical changes. • Atoms are made up of three fundamental particles: electrons, protons and neutrons. • Discharge tube experiments by William Crookes and J.J. Thomson led to the discovery of electron. • Goldstein's experiment with a perforated cathode in the...
CLASS: IX :: Atoms and Molecules
CLASS: IX NCERT (CBSE) Atoms and Molecules SUMMARY • The law of conservation of mass states that the masses of the reactants and products remain unchanged. • The law of constant proportions states that all pure specimens of a compound always contain the same elements combined together in the same proportion by weight. • According to Dalton's atomic theory, all matter is made up...
CLASS: IX :: Is matter around us Pure
Is matter around us Pure CLASS: IX NCERT (CBSE) SUMMARY • Matter is anything that occupies space and has mass • Element is a pure substance, which can neither be decomposed nor built from simpler substances by any physical or chemical means. It contains only one kind of atom. • Broadly speaking, elements can be divided into metals, non-metals, metalloids and noble gases •...
CLASS: IX :: Matter in Our Surroundings
Matter in Our Surroundings CLASS: IX NCERT (CBSE) Chemistry SUMMARY Matter is any substance that has mass and occupies space. Matter is made up of small particles. Solids have definite shapes and volumes. Liquids do not have definite shapes. Liquids do have definite volumes. Gases do not have definite shapes or volumes. Solids cannot be compressed, except porous solids. Liquids take...
