CBSE ADDA

FORCE AND PRESSURE A force is a push or pulls acting on an object which changes or tends to change the state of the object. In the international system of units (SI System), the unit of force is Newton (N) that is named after Sir Isaac Newton. There are also other units like dyne, kilogram weight and pound. Action of force and its effects:  Contact and non-contact forces A force f orces which act only when there is physical contact between two interacting objects are known as c ontact forces.  Forces which can act without physical contact between objects, i.e. those that can act from a distance, are called non-contact forces or field forces. Types of forces 1. Muscular force: This is the force we can exert with our bodies by using our muscles, e.g. pull, push, kick etc. These are contact forces 2. Magnetic force : Magnets exert forces of attraction or repulsion on other magnets. An important feature of magnetic force is that it can act from a distanc

Class 8 S. No. Chapters  Tutorials  Videos  Practice  Interactivities  Assessments   1. Rational Numbers    1     1 1   1    2     2. Linear Equations in One Variable    1    2    3   1 1    2    1   2    3        3. Understanding Quadrilaterals    1    2    3   1    1      1    2    3   4    1      4. Practical Geometry    1    2    3   1            5. Data Handling    1    2    3   1        1    2    3    4  5      1    2    3  6. Squares and Square Roots    1    2    3   1 1    2    3    1    2     1    2     7. Cubes and Cube Roots    1    2    3   1 1   2      1      8. Comparing Quantities    1    2    3     1   1        1    2      1   2    3   4    5  9. Algebraic Expressions and Identities    1    2    3   1 1    2    3 1     1    2  10. Visualising Solid Shapes    1   2     1 1   2   3   4   5    1     11. Mensuration    1    2    3   1     1    2    3    1      12. Exponents and Powers    1    2     1 1    2    3   4 1   2   3    4          13. Direct a