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It is defined as the understanding of biological processes based upon the principles of physics.

For example:

(i) Spectroscopic techniques are used to study the constitution of biological molecules and disorder in them.

(ii) Laws of thermodynamics are used to explain various biological activities of predators and also the activities of molecules.

Dirac’s belief holds true. Equations which represent entire concepts and hold up against experimental results are automatically simple, small and symmetrical, making them truly beautiful. Some examples of beautiful equations are:
E = mc² , E = hv, F = mg, P.E = mgh.

A scientist works for the truth. Every scientific discovery reveals a certain truth of nature. So, any discovery, bad or good for mankind, must be made public.

But with that being said, we cannot afford to be blind to consequences. Before disclosing it we must ascertain the degree of good or bad consequences it will have. If we know that a certain discovery has nothing but dangerous consequences to offer to the mass, the discovery is best kept limited only to the knowledge of the scientist and researches working on it. This way the discovery can help societies in the long run without completely destroying it now.

No difference is noticed in the ability of women and men as far as work, intelligence, decision making is concerned. Nature makes little difference in the anatomy and feeling of men and women. The nutrition content of prenatal and postnatal diet contributes a lot towards the development of a human body. If equal opportunities are provided to both women and men, then the female mind and body will be just as efficient as a man’s. The list of great women who have excelled in their respective fields is enormous. Names of

→ Madame Curie

→ Indira Gandhi

→ Florence Nightingale

→ Margaret Thatcher

→ Mother Teresa,

→ Sarojini Naidu

→ Kalpana Chawla

been taken from fields varying from Sociology to Science and they all very well-known for their contribution to the world.  Reflecting the contribution being made to each and every sphere of life in the country, it can be positively debated that women are no less essential to society than men.

The following are the fields where satellites are being used:

(i) remote sensing, (ii) spying, (iii) Communication, (iv) Weather forecasting.

(i) In remote sensing, infrared photography is used from a high altitude. The technique has improved a lot and the resolution has gone down to about 5 m² in area. This technique has helped in mineral and oil exploration. It has also helped in the study of living beings and crop pattern.

(ii) In the field of communication, satellites have brought revolution during last 20 years.

Now net items are flashed all around the globes. Cricket matches can be watched anywhere on the globe which are played in one small part of a country. Internet, e-mail etc. have brought people much more closer and world has become a unified entity.

(iii) In spying also, we use IR technology.

(iv) Weather forecasting has become more reliable with the use of satellite. The rains, cyclones can now be predicted with greater accuracy 36 hours in advance or even earlier. Movement of glaciers, position of ice and snow deposition and resulting flow of water in rivers is knowing well in advance.

Pauli used the laws of conservation of energy and momentum for β-decay to find neutrino

H. Yukawa discovered Nuclear forces.

Pierre Curie and Marie Curie.

James Chadwick.

Albert Einstein.

(a) The small pox used to kill thousands every year and those who survived,used to get permanently disfigured. Many children become blind and their ears were also affected. Therefore, mass vaccination against small pox is good and welcome. At the time it is heartening to know that this disease is almost eradicated from our country.

(b) The television for eradication of illiteracy and for mass communication of news and ideas is good.

(c) Prenatal sex determination is not good. As only one type of sex (i.e.,son or boy) is preferred in our country, and the girl child is killed. Already the sex-ratio in India is skewed in favour of men.This will create imbalance in population.So, if prenatal sex determination practices is allowed it would be misused creating imbalance in population ratio.

(d) Computers for increase in work efficiency are good.No doubt, there is no chance of personal error and the efficiency increases So it is good.

(e) Putting artificial satellites around earth's orbit will  help us to forecast weather conditions as well as in communication is a welcome and good.

(f) Development of nuclear weapons is not good.These weapons can be used in war to kill millions of innocent people.Not only this,It can destroy buildings, dams cities factories etc. It also destroys crops and farms become infertile.

(g) Development of new and powerful techniques of chemical and biological warfare is not at all good as their use will lead to mass destruction.

(h) An impure and polluted water is the cause of many dreadful diseases. So,purification techniques to purify drinking water is good,for it would destroy the micro-organisms which causes diseases.

(i) Plastic surgery is good.It helps to remove deformation and make people beautiful when used.

(j) Cloning is good as it would improve the health of the generation.

But, if it is misused, then it is lead.

Even though an electron has never been ‘seen’ but its effects have been observed and its practical evidence have been tested and proved. E.g. electricity. However, regarding spirits and ghosts, even though there are many claims and sightings, standardized scientific reading and evidence have never been observed or successfully tested. Thus, we really cannot state with a cent per cent surety that they exist.
 

Yes, there is deep relation between the development of humanity on account of science. Many socioeconomic, political and ethical problems are being tackled and solved by Science. Science has greatly helped in developing the art and culture. Many musical instruments have been developed due to various theories in the physics. The steam engine is inseparable from the industrial revolution which had great impact on the human civilization.

The particles with integral spins are known as Bosons. Boson-Einstein statistics is applicable to Bosons.

Politicians, in this sphere of the world, are always ready to say everything (i,e, honest dishonest, logical or illogical,pure or impure) is possible. That means is politics nothing is impossible. Although something from the point of view of morality, should not be done, but that also can be done by politician.

However, in science, everything can be solved, even impossible and complex phenomena can also be comprehended and solved after scientific studies viz, by observation analysis, formulation and experimentation. For example, Tycho Brahe took observations on Planetary motion for a long period of two years and kepler framed his three famous laws of planetary motion on the basis of this huge store of observation laws. This thus justifies that science is the art of soluble just as politics is the art of the possible.

Physics is the branch of science which deals with the study of the basic laws of nature and their manifestation in different phenomena.

(i) H. Yukawa (ii) James Chadwick, (iii) C.V. Raman (iv) K. Feynman.

Characteristics of electromagnetic force are as follows:

(a) It is a central force.

(b) It obeys inverse square law.

(c) It is both attractive as well as repulsive force.

(d) It is a long range force just like gravitational force

(e) It is a conservative force.

(f) It is 10³⁶ times stronger than the gravitational force.

Nature has gifted us with five sense organs viz.,(a) Eyes, (b) Ears, (c) Tongue, (d) Skin and (e) Nose. We observe and study the nature with the help of all these sense organs. Without these organs it is impossible to study the nature.

(a) If we rub a comb in dry hair the comb and hair begin to attract each other. The force of attraction between a comb and hair is electromagnetic force.

(b) If a magnet is brought near iron pins, the magnet attracts the pins with a force known as electromagnetic force.

One of the definition of physics says that “It is the science based on imagination ad inspection”. Thus, imagination plays an important role in physics.

Geology is the branch of science which deals with the study of earth.

Heresy means anything against the established belief Which creates doubts in the minds of even intelligents whereas dogma implies an established opinion which is questioned by only a few. For example, wave theory of light came into existence only as a heresy in the beginning but finally ended as "dogma" whereas Einstein and other replaced it by quantum theory of light.

Yes, it is imagination, which gives a vivid picture of some scientific theory in the  mind. For example, Huygens' principle, Maxwell's equation, Newton's laws of motion, schrodinger wave equation, Bohr's theory, pauli's exclusion principle etc., were first the imagination of scientists which are successfully employed to explain the various phenomena occurring in nature.

(a) Using electron microscope, we can observe the structure of the cell and structure of micro-organisms.

(b) Radio- isotopes for radiation treatment of cancer and other diseases.

(c) X- ray and neutron -diffraction techniques for studying structure of nuclear acids which control the process of life activity.

Physics is called exact science because it is based on measurement of fundamental quantities.

The main aim of science is to find the truth behind the various processes taking place in the universe.

The Bose-Einstein statistics is applicable to the particles having integer spins called Bosons.

The Fermi- Dirac statistics is applicable to the half integer spin particles satisfying the pauli's exclusion principle.

The universe around us is very complex, the phenomena that are happening are also complex, at the same time the there are large number of basic laws of science. Which govern all these phenomena. So, the things in knowledge, but if we go deeper into the basic laws and analyse explain and associate these phenomena with these laws, then even most incomprehensible thing becomes easy to comprehend and understood .The insight into the fundamental laws of nature of the physical world can be a very exiting of affair.

Supernatural events.

(i) Only qualitative approach is not sufficient so quantitative approach is a must.

(ii) Basic laws are universal so they must be used to explain new or complex phenomena.

(iii) Approximations can be used wherever required to simplify the reasoning for a phenomena.

A person with scientific attitude must have flexible and open-minded approach towards the problems.

Robert hook, England.

Before 1750 A.D.When Industrial revolution took place, simple tools and machines were used. But, industrial revolution brought new machinery.

Some of these outstanding advances of Industrial revolution were:

(a) Powerloom: It was invented in 1785 A.D. by Carl Wright. It used steam power for spinning and weaving.

(b) Steam Engine: It was invented in 1769 A.D. by James watt. It made possible setting of industries in the interior of country,far away from river bank.

(c) Spinning Genny: It was invented in 1764 A.D. by Hargreaves. It speeded up the spinning work.

(d) Flying shuttle : It was invented by John key. It speeded up weaving.

(e) Safety lamp: It was invented by Sir Humphry Davy.It was safely used in mines.

(f) Balast furnace: It enabled industries to produce steel Cheaply.

The systematic observations, controlled experiments, qualitative reasoning, mathematical proofs and prediction is called scientific method.

These books are:

(a) Surely you are joking, Mr Feynman by R.P., Feynman, Banton books (1986).

(b) Mr Tompkins in paperback by G. Gamow, Cambridge University press(1987).

Base or fundamental units = 7 supplementary units = 2.

Significant figures are there in 0.005 is One (1).

S.I. unit of luminous intensity is candela (cd).

[M¹L²T^-2K^-1]

Quantum theory is needed because many phenomena at the microscopic level can not be explained using classical theory, eg: Photoelectric effect, interaction among elementary particles.

The unit of amount of substance is mole.

Joule × second

Chandrashekhar’s limit (1.44 solar mass). 

Conserved quantities are those physical quantities which remain constant in a process i.e. total energy, total momentum, etc.

1 J = 10⁷ ergs.

Three types of errors are there.

Given; t = 2.56 s
speed of light;
v = c = 3 x 10⁸ m/s;

Given equation is, 

Applying principle of homogeneity,

Dimensional formula of a/V² Dimensional formula of P

∴ Dimensional formula of a = Dimensional formula of P.V² 

Similarly dimensional formula of V = [M⁰L³T⁰]

The percentage error in constant K is Zero.