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# Tag Archives: theory

## Was Einstein Wrong?

Was Einstein Wrong? What is the neutrino particle which traveled faster than light?

As we know it now; Neutrino is a neutral subatomic particle with a mass close to zero and half-integral spin, rarely reacting with normal matter.

Three types of neutrinos are known –

Einstein’s theory of relativity suggested that no particle can travel faster than light in vacuum.

If neutrino travels, there is something wrong and we have to make necessary amendments

Further Reference

TWIN PARADOX is a paradoxical situation coming in while explaining the theory of relativity. “Time dilation” is one of the important consequences of relativity. It says that if a body is moving with relativistic speeds, time will dialate for it. That is, a duration of 1 second for him will be more than that for a person at rest or moving at ordinary speeds.

The relativistic time is given by the equation,

So, if we imagine twin brothers, one at rest at earth and other going on a relativistic interstellar trip (certainly he has to go out of solar system as the velocity of light is very much more than escape velocity of solar system, and further, he will reach the sun in just 8 minutes if traveled with the speed of light)

Let us take that his speed is 0.9 times the speed of light in vacuum. Then 1 second for him is equal to 27 s (approximately) for his brother on earth. So, if he returns after one year of space programme, he will be older by 1 year, but his brother who was at home will be older by 27 years or more; if alive.

You are welcome to think of the possibilities of a relativistic travel and the related issues here.

## Is the acceleration due to gravity different in south pole and north pole

“Is the acceleration due to gravity different in south pole and north pole?”

As per theory, acceleration due to gravity changes with altitude, depth and latitude.

If we consider that the variation of g with latitude is caused by rotation of earth only, then the value of g will be same for both north pole and south pole.

But, the change in the value of acceleration due to gravity with latitude is caused by the shape of earth too. So it depends your distance from the centre of earth when you are at north pole or south pole.

For calculations the polar radius is taken same at North as well as south pole. So, value of g can be taken the same for both poles.

## Ideas on the Origin of Universe

Well, nobody knows it exactly. Physics and other sciences can explain How things go or went, not Why. Althought there is a theory, called the M theory or the 11 dimensions theory, that gives a kind of answer to this: the M theory says that the matter is made of little strings that vibrating give to the matter his properties. To ensure all the properties 10 dimensions are necessary: the classical 4 (3 for the space + time) and 6 circumvented dimensions. Well the 10 dimensions theory was not able to explain some phenomenons, as the divergences between relativity and quantum mechanics. in 1995 a phycisist found that assuming the existence of an 11th giant dimension, all was explained. think about this dimension as a giant room where there are sheets hanging from the ceiling. well these sheets are parallel realities. Our universe is in one of these “sheets”. In this frame we have the creation of a universe (a big bang) every time a sheet touches another sheet.

I’ve just described you the frontier of the theoretical physics.

– Daniele G. M / Ancona, Italy

Visitors can respond to the idea given by Daniele

## A question based on the theory of machines

†ђe fig below shows a tilt hammer ahinged at o, with its head resting on top of †ђe pile Bm †ђe hammer including †ђe arm OA, has a mass of 25kg.its centre of gravity Gis 400mm horizontally. from O Ąπϑ its radius of gyration about an axis through G parallel to †ђe axis of †ђe pin 00000 is 75mm. †ђe pile has a mass of 135kg. †ђe hammer is raised through 45• To †ђe position shown in dotted lines Ąπϑ released. On striking †ђe pile there is no rebound. Find †ђe angular velocity of †ђe hammer immediately before †ђe impact Ąπϑ †ђe linear velocity of †ђe pile after impact. Neglect any impulsive resistance offered by †ђe earth into Ψђíçђ †ђe pile is being driven. [Thank you]

## CBSE Rules for Improvement of Performance

Improvement of Performance

Senior School Certificate Examination

**(i) A candidate who has passed an examination of the Board may reappear for improvement of performance in one or more subject(s) in the main examination in the succeeding year only; however, a candidate who has passed an examination of the Board under Vocational Scheme may reappear for improvement of performance in one or more subject{s) in the main examination in the succeeding year or in the following year provided he/she has not pursued higher studies in the mean time. He /she will appear as private candidate. Those appearing for the whole examination may however appear as regular school candidates also if admitted by the school as regular students. In no case, a candidate shall be allowed more than one chance for improvement of his performance.

(ii) For subjects involving practical work, in case the candidate has passsed in practical at the main examination, he/she shall be allowed to appear in the theory part only and marks in practical obtained at the main examination shall be carried forward and accounted for. In case
a candidate has failed in practical he/she shall have to appear in theory and practical both irrespective of the fact that he/she has already cleared the theory examination.

**(iii) Candidates who appear for improvement of performance will be issued only Statement of Marks reflecting the marks of the main examination as well as those of the improvement examination.

***(iv) A candidate appearing for improvement of performance in one or more subjects can not appear for additional subject simultaneously.

## CBSE Rules for Compartment Examinations

Compartment Examination for Secondary/Senior School Certificate Examination

** (i) A candidate placed in compartment may reappear at the compartmental examination to be held in July/August and may avail himself/herself of the second chance in March/April next year and may further avail himself/herself of the third chance at the compartmental

examinations to be held in July/August of that year. The candidate will be declared ‘Pass’ provided he/she qualifies the compartmental subject/subjects in which he/she had failed.

** (ii) A candidate who does not appear or fails at one or all the chances of compartment shall be treated to have failed in the examination and shall be required to reappear in all the subjects at the subsequent annual examination of the Board as per syllabi and courses laid down for the examination concerned in order to pass the examination. The candidate shall have the option to appear at the practical examination in the subjects involving practical or retain their previous marks in one more annual examination after the Third Chance Compartment.

(iii) Syllabi and Courses tor the Compartmental candidates in March Examination shall be the same as applicable to the candidates of full subjects appearing at the examination,

*** (iv) A candidate placed in compartment shall be allowed to appear only in those subjects in which he/she has been placed in compartment at the Second Chance Compartmental Examination to be held in March/April next year.

(v) For subjects involving practical work, in case the candidate has passed in practical at the main examination he/she shall appear only in theory part and previous practical marks will be carried forward and accounted for. In case a candidate has failed in practical he/she shall

have to appear in theory and practical both irrespective of the fact that he/she has already cleared the theory examination.

*** (vi) The candidate who is placed in Compartment in the Secondary School Examination (Class-X) shall be admitted provisionally to class XI till he takes in first chance Compartmental Examination to be held in July/August of that year. His/her admission shall be treated as cancelled if he/she fails to pass at the first chance Compartmental Examination

(For more details visit http://cbse.nic.in/examin~1/scheme06ex.htm )

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