Class 9 Science Chapter 10 Gravitation “Thrust is force acting perpendicular to the surface.” Consider a box kept on table. Box exerts force on table. Therefore, direction of force is perpendicular. Hence, one can say that the box exerts thrust on the surface of table. Effect of thrust It can be demonstrated by very good […]
Physics
What is Energy?
Energy – CBSE Class 9 Science Chapter 11 Work and Energy Energy, force and work are related terms. Consider, the pushing of box. When box is pushed, force is applied and energy is transferred to box. This allows box to move i.e. work is done on box. Hence, energy is defined as, “Capacity of doing […]
Newton’s Laws of Motion
On the basis of observations of Galileo Galilei’s experiment Newton presented three laws of motion. These laws are familiar as Newton’s Laws of Motion. Newton’s Laws of Motion: First Law of Motion Among Newton’s Laws of Motion, first law of motion states that, “Body tries to maintain its state of rest or uniform motion along […]
Refraction of light
Refraction of light is change in direction of light while travelling from one medium to another. For example: pencil if placed half immersed in water appears to be bent. Not only pencil but anything kept half immersed in water appears to be bent. Moreover, extent of change in direction of light changes from medium to […]
What is Gravitation?
Presence of gravitation or gravitational force was first brought up by Sir Isaac Newton. Story of falling of apple on Newton’s head is very much familiar. Apple fell on head of newton, on basis of this observation, he carried out experiments. Moreover, the experiments revealed the existence of gravitational force on basis of which universal […]
Ohm’s Law – Relation between Resistance, Potential Difference and Current
Ohm’s law determines the relation between the potential difference and the flow of current. Therefore, Ohm’s law states that, “ At constant temperature potential difference(V) is directly proportional to current (I)” V∝ I Verification of Ohm’s Law At constant temperature, if we plot a graph of current versus potential difference, a straight line graph passing […]
What is Motion?
A body is said to be in motion, if it changes its position with respect to time. If not so, then body is said to be at rest. A racing car, flying aeroplane, flowing rivers, rolling ball are all in motion whereas, a standing bicycle, a tree, wall of room are at rest. To understand […]
What is Physics?
Introduction to Physics Physics is the study of basic laws of nature and their expression in different natural phenomena. For instance, Newton studied the fall of apple to the ground, and formulated, the “ Laws of Gravitation ”. This law helped to explain different natural phenomena like why things do not escape in space on […]
What is Projectile Motion?
Have you ever observed that, When you kick a football it travels in a curved path. The particle that travels the curved path is called the projectile. The motion of projectile is called Projectile motion. The motion of the particle can be studied separately for horizontal and vertical parts. The point of projection is taken […]
Heating Effect of Electric Current
While dealing with electricity a very important phenomena is heating effect of electric current . Whenever there is current flow there is motion of electrons. During their journey electrons collide with other electrons, atoms or ions present in the conductor. At each collision, a part of the kinetic energy i.e. energy of a moving electron […]