Test: Physical World - 2 (Old NCERT) - JEE MCQ

The natural sciences seek to understand how the world and universe around us works. There are five major branches (top left to bottom right): Chemistry, astronomy, earth science, physics, and biology.

Microscopic domain includes atomic,molecular and nuclear phenomena. It can be said as the study of matter.It includes the study of structure and configuration of atom,nucleus and the constitute particles of atom-electron,proton,neutron and interaction with elementary particles like electron,photon etc.

The history of technology is the history of the invention of tools and techniques and is similar to other sides of the history of humanity. Technology can refer to methods ranging from as simple as language and stone tools to the complex genetic engineering and information technology that has emerged since the 1980s.

In addition to intense heat, there is an incredible amount of pressure at the Sun's core. In fact, the vast amounts of hydrogen atoms in the Sun's core are compressed and heated so much that they fuse together.This reaction, known as nuclear fusion, converts hydrogen atoms into helium. The by-product of nuclear fusion in the Sun's core is a massive volume of energy that gets released and radiates outward toward the surface of the Sun and then into the solar system beyond it.

Science is a systematized study of observation. Scientist and researchers study these observations and then work out certain laws from them. There are multitude of natural phenomena taking place in this universe and all of them can be explained in terms of some basic laws.

The phrase "scientia potentia est" (or "scientia est potentia" or also "scientia potestas est") is a Latin aphorism meaning "knowledge is power"

Quantum mechanics (QM -- also known as quantum physics, or quantum theory) is a branch of physics which deals with physical phenomena at nanoscopic scales where the action is on the order of the Planck constant. It departs from classical mechanics primarily at the quantum realm of atomic and subatomic length scales.

Technology is often a consequence of science and engineering, although technology as a human activity precedes the two fields. For example, science might study the flow of electrons in electrical conductors by using already-existing tools and knowledge. This new-found knowledge may then be used by engineers to create new tools and machines such as semiconductors, computers, and other forms of advanced technology.

The weak nuclear force stops a neutron from decaying into a proton and an electron. When this happens, an electron leaves the atom. This is known as beta decay.

It is simply a superstition that ghost exist. There is not even single authentic evidence that ghosts exists. On the other hand it is a fact that atoms exists. There are many examples to prove this fact. Atomic power plant, atomic bombs, atomic clocks etc., exist of the correlation between two parts of the statement.

The scientific method is a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry is commonly based on empirical or measurable evidence subject to specific principles of reasoning.

Quantitative measurement is central to the growth of physics because Laws of nature happen to be expressible in more precise mathematical equations.

Science and technology will continue to generate all sorts of new enhancers, and the quest for enhancement is not necessarily unfair or unethical. We humans are inveterate enhancers, striving to increase our intelligence and to improve our memory and powers of perception.

The nuclear force does not depend upon the charge of nucleons.Nuclear forces usually depend upon the velocity of the nucleons.

In 1957, the world was surprised to see the Soviets launch the first satellite into orbit, with most expecting the USA to be the first to do so .Setallite technology got wings after this year which is so far after industrial revolution in England and Europe.

The scientific method starts when you ask a question about something that you observe: How, What, When, Who, Which, Why, or Where? For a science fair project some teachers require that the question be something you can measure, preferably with a number. 

Laws of nature as expressed in physics as laws and theories are often said to be universal. This means that, so far as we have been able to test them, they apply everywhere and at every time, past, present and future.

Thomas Newcomen's atmospheric engine was the first commercial true steam engine using a piston, and was used in 1712 for pumping in a mine. 

There are four fundamental forces in nature which are Gravitational force, Strong force, Weak force and Electromagnetic force.

Gravitational Force: This force is the weakest but has an infinite range.

Strong Nuclear force: This force holds the nucleus of an atom together. It is the strongest of the forces. It acts over a range of about 10-15m.

Weak Nuclear Force: This force is weak compared to the strong force as the name implies and has the shortestrange of 10-18m

Electromagnetic Force: This is the second strongest force after the strong force and it acts on electrically charged particles. It has strength of 1/137 relative to the strong force but has an infinite range.

By the 1780s, the British Industrial Revolution, which had been developing for several decades, began to further accelerate. Manufacturing, business, and the number of wage laborers skyrocketed, starting a trend that would continue into the first half of the 19th century. This was the time when Louie Pasteur discover the link between microbes and illness.

A scientific theory is an explanation of some aspect of the natural world that can, in accordance with the scientific method, be repeatedly tested, using a predefined protocol of observations and experiments.Established scientific theories have withstood rigorous scrutiny and are a comprehensive form of scientific knowledge.

It is not practical to take into account all the complexities of a phenomenon in one go.A good and scientific strategy is to focus first on the essential features, discover the basic principles and then introduce corrections to build a more refined theory of the phenomenon by removing its less significant aspects.

The macroscopic domain includes everyday and laboratory chemistry, where we observe and measure physical and chemical properties, or changes such as density, solubility, and flammability.

In physics, a conservation law states that a particular measurable property of an isolated physical system does not change as the system evolves over time. Exact conservation laws include conservation of energy, conservation of linear momentum, conservation of angular momentum, and conservation of electric charge.

The Suśruta-saṃhitā is one of the most important surviving ancient treatises on medicine and is considered a foundational text of Ayurveda. The treatise addresses all aspects of general medicine, but the translator G. D. Singhal dubbed Suśruta "the father of surgery" on account of the extraordinarily accurate and detailed accounts of surgery to be found in the work. He has also been called "the first plastic surgeon".

A scientific theory is not the end result of the scientific method; theories can be proven or rejected, just like hypotheses. Theories can be improved or modified as more information is gathered so that the accuracy of the prediction becomes greater over time.

In physics, we can neglect some small forces, quantities and calculation.

The Indian physicist C.V. Raman helped the growth of science in his country. He received the Nobel Prize for Physics in 1930 for the discovery that when light passes through a transparent material, some of the light changes in wavelength. This phenomenon is now called Raman scattering.

Mechanical energy is the sum of the potential and kinetic energies in a system. The principle of the conservation of mechanical energy states that the total mechanical energy in a system (i.e., the sum of the potential and kinetic energies) remains constant as long as the only forces acting are conservative forces.

Science can help us learn about terminal illnesses and the history of human and animal rights — and that knowledge can inform our opinions and decisions. But ultimately, individual people must make moral judgments. Science helps us describe how the world is, but it cannot make any judgments about whether that state of affairs is right, wrong, good, or bad.