CBSE Class 9 Science Motion Notes
MOTION INTRODUCTION Motion is a very preliminary state of action associated with living and non-living beings. The study of the displacement, velocity and acceleration associated with moving bodies can make us understand the motion of bodies. To have an in-depth study of…
CBSE Class 9 Science Wave Motion And Sound Notes
WAVE MOTION AND SOUND NATURE OF SOUND Sound is a form of energy which effects our sensation of hearing through the ear. The sensation is produced by longitudinal waves in an elastic medium, where the vibrations (oscillations) of the particles are in the same direction in which…
CBSE Class 9 Science Work Energy And Power Notes
WORK, ENERGY AND POWER INTRODUCTION In everyday language, the word work is used to describe any activity in which muscular or mental effort is exerted. In physical, the word work has a special meaning. Work in one done when the force acting on body produced motion in it in the…
CBSE Class 9 Science Gravitation And Fluid Notes
GRAVITATION AND FLUID INTRODUCTION Besides developing the three laws of motion, Sir lssac Newton also examined the motion of the heavenly bodes - the planets and the moon. Newton recognized that a force of some kind must be acting on the planets to keep them in nearly circular…
CBSE Class 9 Science Force And Laws Of Motion Notes
FORCE AND LAWS OF MOTION FORCE Consider a ball kept on a table, we can move it by pulling or pushing. We can increase its speed by pushing it in the direction of motion. If we push it opposite to the direction of motion its speed will decrease. If the ball is in motion towards…
CBSE Class 9 Science Physical Science Notes
PHYSICAL SCIENCE 1.MITOCHONDRIA (POWER HOUSE OF THE CELL)It was first seen by kolliker and named by BendaThey are small rod-shaped organelles.It is a double membrane structure with outer membrane being smooth and porous whereas inner membrane being thrown into a number of…
CBSE Class 9 Science Structure Of Atom Notes
STRUCTURE OF ATOM INTRODUCTION (i) The idea of tiniest unit of matter (Anu and Parmanu) was propounded by maharishi Kanad in Vedic period in our country. (ii) Democritus, a Greek philosopher also proposed that matter is made up of extremely small particles, the “atom”. The…
CBSE Class 9 Science Atoms And Molecules Notes
ATOMS AND MOLECULES INTRODUCTION It was proposed by Indian philosopher, maharishi Kanad, that if we go on dividing matter, we will get smaller and smaller particles of matter. Finally, we will get the smallest particle of matter, which cannot be divided further. John Dalton …
CBSE Class 9 Science Is Matter Around Us Pure Notes
IS MATTER AROUND US PURE General characteristics of mixtures1. During the formation of a mixture, the components do not react chemically.2. The composition of mixture is not fixed, i.e., the components may be present in any proportion by mass.3. The [proportion of a mixture…
CBSE Class 9 Science Matter In Our Surroundings Notes
MATTER IN OUR SURROUNDINGS INTRODUCTION There are a large number of things around us which we see and feel. For example, we can see a book in front of us. A book occupies some space. The space occupied by the book is called it volume. If we pick up the book, we can also feel…
CBSE Class 9 Science Improvement In Food Resources Notes
IMPROVEMENT IN FOOD RESOURCES INTRODUCTION food is the combination of various organic and substances which is capable of providing energy for the various metabolic activates. materials for repair / replacement of worn-out tissues in the body. materials for growth…
CBSE Class 9 Science Natural Resources Notes
NATURAL RESOURCES NATURAL RESOURCES It indicates the potential wealth of a country. The variety of substance that man gets from earth and nature to meet his basic needs are called natural resources. The word resource means a source of supplying a material generally held in…
CBSE Class 9 Science Why Do We Fall Ill Notes
WHY DO WE FALL ILL HUMAN HEALTH…
CBSE Class 9 Science Diversity In Living Organisms Notes
DIVERSITY OF LIVING ORGANISMA DIVERSITY AND CLASSIFICATION Diversity means = variety. Different places on the earth have their own typical kinds of living beings. This gives rise to the need of classification. So “Diversity is the need of classification”. Classification is…
CBSE Class 9 Science Tissue Notes
TISSUE INTRODUCTION In unicellular organisms a single cell performs all the vital activities for example, digestion, respiration, excretion etc. In case of Multicellular organisms specialized functions are performed by a different groups of cells. As blood flows for…