What is a Wave?Figure shows water waves being formed when a few drops of water fall onto the surface of a pond. A wave is a travelling disturbance from a vibrating or oscillating source. As a wave travels, it carries energy along with it in the directio…

Understanding Gas PressureFigure shows a boy pressing the front tyre of his bicycle. (a) When he presses the tyre with his thumb, he feels an opposing force acting on his thumb. (b) The force is due to the air pressure in the tyre. (c) The air pressure …

What do you mean by Total Internal Reflection?The inside surface of water can act like a perfect mirror as shown in Figure. This happens when the light rays strike the surface of the water in such a way that it reflects back into the water.The light rays…

What Is Potential EnergyPotential Energy: Thus the energy possessed by a body by virtue of its position or change in shape is known as potential energy. It is obvious that a body may possess energy even when it is not in motion.Expression for Potential …

Natural Phenomenon due to Refraction of LightShallow Swimming PoolsFigure shows a swimming pool appearing to be shallower than it really is. This is due to the light rays from the bottom of the pool being refracted away from the normal as they enter the …

What is the Hooke’s Law?Hooke’s law states that the extension of a spring is directly proportional to the applied force provided the elastic limit is not exceeded.Figure shows a graph of extension, x of a spring against applied force, F. (a) The portion …

Applications of Pressure in Daily Life Some of the applications of pressure are given below.The area of the edge of a knife’s blade is extremely small. This creates a pressure high enough for the blade to cut through a material.Syringes are used to take …

Measurement of Time Using Periodic MotionAny object that is moving is said to be in motion. In order to measure time, we need a motion that repeats itself in equal intervals. Such a motion is called periodic motion.Some examples of periodic motion are th…

Examples Of Non Contact ForcesForces that do not need physical contact with the object on which they are acting are called non-contact forces. Gravitational force, electrostatic force, and magnetic force are examples of non-contact forces.Gravitational …

Refraction Of Light Through A Glass SlabRefraction through a rectangular glass slab and principle of reversibility of light: Consider a rectangular glass slab, as shown in figure. A ray AE is incident on the face PQ at an angle of incidence i. On enterin…