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In the study of motion, there are two quantities we should understand, these are the scalar and vector quantities. A scalar quantity is described by its magnitude only while a vector quantity has both magnitude and direction. Force, velocity, acceleration, displacement and electric field are vector quantities. Speed, distance, mass, volume, time density are some examples of scalar quantities.
Consider a ball sliding down a very smooth, frictionless inclined plane. Due to a constant force action in the ball, it's velocity increases as it moves along the plane. The velocity of an object is continuously changing either in its magnitude or in its direction or in both. We defined acceleration as the time rate of change or velocity or Acceleration is equal to Change in Velocity divided by the Elapsed Time.
An object in motion is said to be accelerated when it's velocity increases in magnitude or direction or in both. Examples of accelerated motion are falling objects and ball rolling down an incline plane. The velocity of a body may be changed by changing the speed, the direction, or both speed and direction. If the direction of the acceleration is parallel to the direction of motion, only the speed changes; if the acceleration is at right angles to the direction of motion, only the direction chan...
Forces affect objects in many ways. These can be categorized into two: Change in shape and change in motion. In fact, forces cannot be seen but can only be inferred through the effects that they manifest. One of the most thrilling experiences you can get from riding a roller coaster is momentarily upside down, without falling out.
'Escape velocityâ€™is a direct application of Newtonâ€™s third law as the force exerted by the body escaping from the earth generates a reaction. This force or velocity generated must be greater than the attracting force for an object to break free and enter space. It has now been calculated that a velocity of 7 miles per second is the minimum speed required to break free from the confines of the earthâ€™s gravity; this is popularly referred to as ' Escape velocity' and works out...
Quantum harmonic oscillator has a great importance in physics because of its application in a wide variety of problems. In this article I have discussed how to quantize a harmonic oscillator and find its eigenstates and eigenenergies by the using the so called ladder operator prescription. Then the result is generalized to the case of multidimensional harmonic oscillator.
The Atomic bomb was first used on Japan and resulted in unconditional surrender. The A-Bomb is based on Einsteinâ€™s energy mass equation. It involves bombarding the heavy nuclei of an element like Uranium or Plutonium with neutrons. This sets off a chain reaction called fission resulting in a massive release of energy. It also releases gamma rays and neutron radiation called fallout.
The analysis of current distribution in a circuit of normal conductors is done by help of Ohmâ€™s law, Kirchhoffâ€™s laws and other network theorems but trivial use of these laws in case of a resistanceless circuit lead to wrong results. For the case of normal conductors currents are mainly determined by the resistances but in a resistanceless circuit we need to consider self-inductances and mutual inductances also. This article describes the analysis of such non-trivial cases.
In 1908 a mysterious blast took place in Tunguska, Siberia when a body from space exploded before it hit the earths crust. This resulted in a blast of the magnitude of 1000 A bombs dropped on Hiroshima. The incident has fired the imagination of scientists who have given varied theories for the explosion. Many have opined that the blast was caused by a alien spaceship while others have concluded it was a body from space.
The earliest sources of magnetism were magnets such as the famous loadstone of Magnesia. Many scientists began investigating the properties of magnetism associated with electric currents when they discovered that a compass needle is deflected by an electric current. One of the objective of this experiment is to differentiate magnetic induction from magnetism. Continue reading to know more.
The invisible something that enables magnet to pull or push other objects is called magnetism. It cannot be heard, seen, smelled, tasted, or directly felt, and it does not have any weight. If you could take apart all the devices that use electric current to produce motion, you would find that nearly all of them contain one or more magnets.The objective of this experiment is to be able to find out the directions of magnetic lines of force around a wire carrying current.
Modern airliners have complex avionic systems. These need to be monitored for proper efficacy. This is done by Numerik Control systems called open and closed loops. These are important because of the power electronic on board. The open and closed loops systems help compare the operating parameters of the aircraft
In the study of motion, there are two quantities we should understand, these are the scalar and vector quantities. A scalar quantity is described by its magnitude only while a vector quantity has both magnitude and direction. Force, velocity, acceleration, displacement, and electric field are vector quantities. Speed, distance, mass, volume, time, density are some examples of scalar quantities. The objective of the experiment is to determine the direction of the resultant force of a simple force...
Almost everything around you can be measured. The clothes you wear, the food you eat, the distance between two planets or even the width of a bacteria can be measured. Physics as a science involves measurement. By measurement, we mean comparison with a standard. One of the objective of this experiment is to measure the length of some objects accurately. And to know the relationship of the metric system to English system of units.
Mathematica has a beautiful implementation of graph plotting which is used worldwide by scientists, students, engineers in various fields of their work. Multiple graph plotting, piecewise graph plotting, manipulation of a plot, parametric graph plotting, graph plotting by importing data from a file etc. can be done very easily in Mathematica.
Have you ever wondered why you are safest in a car when out in a thunderstorm? You may have thought that it is the rubber tires that protect you, and that might be partly true. Tires are a fairly good insulator. However, the reason that you are safe in a car is due to the law of FaradayÂ’s Cage.
What are the supporting arguments for the big crunch theory, and has it ever been proven wrong?
Learn how electromagnetic energy affects the Pineal Gland in the human body and how the Calcite Micro-crystals respond and reproduce electromagnetic energy.
Steep gradients can be overcome by the use of rack equipment; however it is not practical to equip all locomotives with such equipment. The list below is of some of the steepest gradients on adhesion railways.
Einstein's energy mass equation is the most important development after Newton's Force equation. It brought in the concept of light as a fundamental constant.
Machines make the difficult things done easier. These things are used in different fields of activity to be able to make thing easily done. There are many different machines and all of these have their different functions.
Bhabha-Heitler theory of cosmic showers is important as it gives us an understanding of the nature of Cosmic rays
Newtons Laws of motion have universal applicability and understanding them is of paramount importance in today's world
The Raman effect deals with change of wavelength after scattering of light, which passes through a medium
explaining the kinetic theory and brownian motion
The sun is the major source of energy. The suns solar energy is one of the factors that support life in our planet. The plants that we eat absorb energy from the sun as these plants make their own food
What is a semiconductor? what are the types of a semiconductor?
There are different kinds of energy source in the environment. Perhaps, the most commonly used form of energy is the electrical energy. Electrical energy is the energy that we always used in day to day activity. It became one of the basic needs of man specially when in this technological age.
Contrails: What Are They?, Contrails and issues about them
In 1928, in France, a Neuchatel engineer called Jean-Leon Reutter built a clock driven quite literally by air. This clock could run for several centuries without wearing out or requiring any winding, battery power or electricity.
In November of 1677, the Royal Society turned to Robert Hooke to duplicate AntoniÂ’s results. Robert Hooke was an English natural philosopher, architect and polymath who played an important role in the scientific revolution, through both experimental and theoretical work. He was first to use the word "cell" to apply to a basic unit of life. He wrote the book "Micrographia".
Friction is an every day occurrence and has a lot of importance. It can be measured by a Tribometer
Learn about the crystal physics, Piezoelectric Effect and metaphysical properties of Clear Quartz Crystal which is also known as Rock Crystal Quartz or Rock Crystal. Learn how Quartz was used in history as well as the purpose and benefits of those who use it for meditation, dream work and energy work.
New scientific experiments have developed an invisibility cloak which can hide everyday objects from the human eye, by using calcite and bending light.
Professor Stephen Hawking, of Cambridge University, England, has been given the Â“Einstein AwardÂ”. This is very high honour. Professor Hawking is an expert on Black Holes. The idea of Black Holes is very strange. A French scientist first suggested it in 1796. He suggested that light is attracted by gravity. If a star has very powerful gravity, the light cannot escape. The Â“escape velocityÂ” (which means, the speed necessary to leave the star) is greater than the speed of light. Thi...
How tycho brahe and johannes kepler contributed to science, and how tycho proved aristotle wrong.
In a laser, such as a gas discharge type laser like a mercury vapor discharge lamp, the light from the atoms is reflected to and fro between two mirrors facing each other, and is amplified (concentrated to make it more powerful) as it passes through the gas in the discharge. The lased (amplified) beam of light is so bright that it can be used to send messages to the moon or to more distant parts of the solar system.
Multiple universe and alternate reality
Observations on the effects of hot or cold on a rubber band: a simple Physics experiment and entropy.
Why is it that when we look at televised activities of astronauts, they seem to be weightless and floating around in space? And why do bodies become weightless in space? Well the common answer will be to say that this is because there is no gravity in space or that the gravitational force is at a minimum due to the distance between the object from the center of gravity. But then is this correct?
What is Antimatter? A simple discussion of what is matter and antimatter as well as well as potential uses in harvesting antimatter.
The Man of Speed, Ernst Mach and the Mach Number
Is invisibility possible?
E=MCÂ² is an expression widely known but little understood by most who quote this expression. Interestingly, this is an algebraic expression that opened the world to things as good as nuclear energy and things as awful as nuclear bomb.
The emission of electrons from metals heated above 1000 degree centigrade is called thermionic emission. The name is made of thermo (heat) and ion (charged particle). See an introduction here.
Today everyone knows that electrons and protons are constituents of atom, but what exactly is an electron. How exactly did they discover it?
A discussion of one philosopherÂ’s painful explanation of the process we label as time.
Resonance of sound waves is an effect which makes all the beautiful sounds around us possible. If you love the sound of pipe organ, you should give thanks to resonance.
This article covers Newton's laws and their implications to modern and ancient science.
Elasticity is a very interesting word. It came into everyday vocabulary from science, and has acquired a meaning that is totally opposite to the original meaning.