Skip to main content


True Discount and Banker's Discount problems tricks in Hindi | fast track formulae for problem solving.


TRUE DISCOUNT 1). वास्तविक बट्टा = मिश्रधन - वर्तमान धन
2). यदि ब्याज की दर r% वार्षिक , समय t व वर्तमान धन (pw) है, तो वास्तविक बट्टा = PW×r×t/100
3). यदि r% तथा समय t के बाद देय धन A है, तो तत्काल धन pw = 100×A/(100+r.t)
4). यदि देय धन A पर r% व समय t दिए गए है, तो वास्तविक बट्टा = A.r.t /(100+r.t)
5). यदि किसी निश्चित समय के पश्चात निश्चित वार्षिक दर पर, देय धन पर वास्तविक बट्टा (TD) व समान समय व दर के लिए साधारण ब्याज (SI) हैं, तो देय धन A =      SI × TD/(SI - TD)
6). यदि t समय पश्चात r% वार्षिक दर पर, देय धन पर वास्तविक बट्टा (TD) व साधारण ब्याज (SI) है , तो -  SI - TD = TD×r×t/100
7). t वर्ष बाद r% चक्रवृद्धि दर पर देय धन A का तत्काल धन (PW) = A/(1+r/100)^t   व वास्तविक बट्टा = A - PW
BANKER'S DISCOUNT1). महाजनी बट्टा = शेष समय (समाप्त न हुए समय) के लिए बिल पर ब्याज = बिल की राशि × दर × शेष समय /100
2). महाजनी लाभ = महाजनी बट्टा - वास्तविक बट्टा
3). यदि बिल का मान / अंकित मूल्य A है, समय t व दर r% है, तो महाजनी बट्टा = A×r×t/100

CORONA VIRUS, history of origin , discovery , infection mechanism, symptoms and treatment.

Today we are going to talk about a virus , which is spreading very fastly all over the world. The virus which we are going to talk about is the CORONA VIRUS. So today we will talk about everything of this virus. So let's starts ...
CORONA VIRUS - A BIOLOGICAL DISASTER | Let's Know Everything About It.


According to the biological study , Coronavirus is a cluster of viruses that causes diseases in birds and mammals. Therefore humans are also mammals then in human being this viruses cause respiratory infections , and one of the respiratory infections is mild common cold. Coronavirus can lead to diarrhea in cows and pigs but in chicken they can cause upper respiratory infections. Currently there is no vaccine or antiviral drugs for the treatment of diseases caused by Coronavirus.


The family of Coronavirus is coronaviridae, and it's subfamily is Orthocoronavirinae and order is Nidovirales, Coronavirus is a member of Orthocoronavirinae subfamily. All Coronavirus is coated with positive sense single strained RNA genome and nucleocapsid of helical symmetry.
Coronavirus has genomic size of approximately 26 to 32 kilobases, but RNA viruses have largest genomic size. If we talk about its nomenclature then , Coronavirus is derived from Latin word Corona , which means crown or halo. Which is attributed to the royal appearance of this viruses or virus particles ( virions). 


CORONA VIRUS - A BIOLOGICAL DISASTER | Let's Know Everything About It.

Now let's talk about the infection mechanism of Coronavirus , the cell of the Coronavirus is uncoated and it's RNA genome is deposited into the cytoplasm. The RNA genome of Coronavirus has 5 methylated cap and 3 polyadenylated tail which helps the RNA to attach to the ribosome for translation purpose.
This virus has also a protein which is known as replicase , which is encoded into its genome and helps RNA viral genome to transcribed into a new RNA copies by using the host cell machinary. When once the translation process of gene encoding completed, then translation is stopped by a stop codon. This is known as nested transcripts. Encoding of only one gene by mRNA transcript is called monocistronic. The protein of Coronavirus has not a definite shape, due to this ,,this replicase protein provide a extra fidelity to replication, because it offer a proofreading function. After replication of RNA genome a long chain of polyprotein is formed , where all protein is attached. Protease, a non structural protein has ability to seperate the protein in the chain, this form is called the genetic economy of the virus, which helps the viruse to encode the greatest number of genes in a single nucleotide.


CORONA VIRUS - A BIOLOGICAL DISASTER | Let's Know Everything About It.
Biologists discovered the Coronavirus in 1960s. But one of the earliest discovered Coronavirus is infectious bronchitis viruse in chickens and two viruses are discovered from the nasal cavities of human patients , which were suffering from common cold , and subsequently this two viruses are named as human Coronavirus 229E and human Coronavirus OC43. And in coming years different Coronavirus are discovered which lies in the same family as of two above human Coronavirus. The new discovered Coronavirus are SARS - coV in 2003, HcoV - NL63 in 2004, HKU1 in 2005, MERS - CoV in 2012 and 2019 - nCoV in 2019. These later discovered viruses are found to be involved in critical respiratory tract infections.


According to the biological study , the most recent common ancestor (MRCA) of Coronavirus has been found approximately around 8100 BCE.
Coronavirus has different categories that is , alphacoronaviruse , betacoronaviruse, gammacoronaviruse and deltacoronaviruse and their MRCA has been found about 2400 BCE , 3300 BCE , 2800 BCE and 3000 BCE. respectively. In the study it is found that bats , birds and other warm blooded flying vertebrates are ideal host of Coronavirus gene. Bats are ideal host for alphacoronaviruse and betacoronaviruse , and birds are ideal host for gammacoronaviruse and deltacoronaviruse. This host helps Coronavirus to evolute in a advanced one.
Bovine Coronavirus and canine respiratory Coronavirus diverged from a common ancestor in 1951. Bovine and human Coronavirus OC43 diverged in 1899 , if we talk about the Bovine Coronavirus then it is diverged from a equine Coronavirus species at the end of 18th century. Some biological researchers believed that human Coronavirus OC43 diverged from Bovine Coronavirus in 1890. And the MRCA of human Coronavirus OC43 has been labeled to the 1950s. Biologists believed that Coronavirus evolved with bats and ancestor of SARS viruses for a long time and first infected the species of the gene Hipposideridae and subsequently spread to the species of Rhinolofidae and then to the civets and from civets it spread ultimately to the humans , in the form of human Coronavirus .
Now let's talk about the human Coronavirus.


In human beings the major impact of Coronavirus are on respiratory system. In human beings it can cause common cold to all age categories of peoples. It can give respiratory infections to children as well as adults. 
There are seven strains of human Coronavirus , which is:
1). Human Coronavirus 229E (HCoV - 229E)
2). Human Coronavirus OC43 ( HCoV - OC43)
3). SARS CoV
4). Human Coronavirus NL63 ( HCoV - NL63)
5). Human Coronavirus HKU1
6). Middle East respiratory syndrome Coronavirus. ( MERS - CoV)
7). Novel Coronavirus ( 2019 - nCoV)
Novel Coronavirus is also known as Wuhan pneumonia or Wuhan Coronavirus. (Novel means newly discovered)
The major symptoms of Coronavirus infections in human beings is given ahead.
If you see any of these symptoms then you should immediately consult to a doctor. Never ignore these symptoms. 


*  It leads to fever.
* Swollen adenoids of thorat.
* It can cause pneumonia ( direct viral pneumonia or secondary bacterial pneumonia)
* It can cause bronchitis ( direct viral bronchitis or secondary bacterial bronchitis)
* Shortness of breath
* Sore throat
* Coughing
* Running nose
*Difficulty in breathing
* Headache
* Feeling of unwell


Human Coronavirus can be spread through contagious and non contagious mode of transmission , it can include

1). By air during coughing and sneezing.
2). By personal contact : touching or shaking hands.
3). Touching the virus contaminated objects.
4). It can rarely transmitted through fecal matters.
5). Eating not properly cooked meat of birds or pigs and goats.


Currently there is no any vaccine or antiviral drugs for the treatment of patients which are suffering from diseases caused by the Coronavirus. May be in future , a proper treatment would be introduce regarding to this Coronavirus. So till now prevention is best cure. Here some important prevention methods are given , which you can follow to reduce the infections.

1). Wash your hands properly with disinfectant soap before and after doing some work.
2). Avoid touching any any person which is suffering from any kind of diseases, specially nose, mouth, eyes and hands.
3). Stop eating food with someone else. Eat food individually.
4). Keep yourself hydrated , stay at home.
5). If you feeling unwell then immediately consult with your doctor.
6). Never ignore any symptoms.
And most importantly BE OPTIMISTIC ...



Boat and stream short-tricks in Hindi | Fast track arithmetic formulae for competitive examination.

BOAT AND STREAM (नाव एवं धारा)
1). यदि शांत जल में नाव या तैराक की चाल x किमी/घंटा व धारा की चाल y किमी/घंटा है, तो धारा के अनुकूल नाव अथवा तैराक की चाल = (x+y) किमी/घंटा
2). धारा के प्रतिकूल नाव अथवा तैराक की चाल = (x-y) किमी /घंटा
3). नाव की चाल = (अनुप्रवाह चाल + उद्धर्वप्रवाह चाल)/2
4). धारा की चाल =  (अनुप्रवाह चाल - उद्धर्वप्रवाह चाल)/2
5). यदि धारा की चाल a किमी/घंटा है, तथा किसी नाव अथवा तैराक को उद्धर्वप्रवाह जाने में अनुप्रवाह जाने के समय का n गुना समय लगता है,(समान दूरी के लिए), तो शांत जल में नाव की चाल = a(n+1)/(n-1) किमी/घंटा
6). शांत जल में किसी नाव की चाल x किमी/घंटा व धारा की चाल y किमी/घंटा है, यदि नाव द्वारा एक स्थान से दूसरे स्थान तक आने व जाने में T समय लगता है, तो दोनो स्थानों के बीच की दूरी = T(x^2 - y^2)/2x km
7). कोई नाव अनुप्रवाह में कोई दूरी a घंटे में तय करती है, तथा वापस आने में b घंटे लेती है, यदि नाव कि चाल c किमी/घंटा है, तो शांत जल में नाव की चाल = c(a+b)/(b-a) km/h
8). यदि शांत जल में नाव की चाल a किमी/घंटा है, तथा वह b किमी/घंटा की चाल से बहती हुई नदी में गत…

Emergence of British East India Company as an Imperialist Political Power in India

Dynamically changing India during early eighteenth century had a substantially growing economy under the authority of Mughal emperor Aurangzeb. But after his demise in 1707, several Mughal governors established their control over many regional kingdoms by exerting their authority. By the second half of eighteen century, British East India Company emerged as a political power in India after deposing regional powers and dominating over Mughal rulers. The present article attempts to analyze the reasons for emergence of British East India Company as an imperial political power in India and their diplomatic policies of territorial expansion. In addition to this, I briefly highlighted the Charter Acts (1773, 1793, 1813, 1833 and 1853) to trace its impact on the working process of Company.Establishment of East India Company in India

In 1600, British East India Company received royal charter or exclusive license…

Three dimensional geometry (part-1) | study material for IIT JEE | concept booster , chapter highlights.


In the following diagram X'OX , Y'OY and Z'OZ are three mutually perpendicular lines , which intersect at point O. Then the point O is called origin.
In the above diagram X'OX is called the X axes, Y'OY is called the Y axes and Z'OZ is called the Z axes.
1). XOY is called the XY plane. 2). YOZ is called the YZ plane. 3). ZOX is called the ZX plane.
If all these three are taken together then it is called the coordinate planes. These coordinates planes divides the space into 8 parts and these parts are called octants.
COORDINATES  Let's take a any point P in the space. Draw PL , PM and PN perpendicularly to the XY, YZ and ZX planes, then
1). LP is called the X - coordinate of point P. 2). MP is called the Y - coordinate of point P. 3). NP is called the Z - coordinate of the point P.
When these three coordinates are taken together, then it is called coordinates of the point P.

Speed , Distance and Time problems tricks in Hindi | fast track arithmetic formulae for problem solving.

1). दूरी = चाल × समय
2). समय = दूरी/चाल
3). चाल = दूरी/समय
4). किलोमीटर को मील बनाने के लिए गुना किया जाता है =       5/8 से
5). मील को किलोमीटर बनाने के लिए गुना किया जाता है =       8/5 से
6). फुट - सेकंड को मील - घंटा बनाने के लिए गुना किया जाता है = 15/22 से
7). मील - घंटा को फुट - सेकंड बनाने के लिए गुना किया जाता है = 22/15 से
8). मी - सेकंड को किमी - घंटा बनाने के लिए गुना किया जाता है = 18/5 से
9). किमी - घंटा को मी - सेकंड बनाने के लिए गुना किया जाता है = 5/18 से
10). यदि एक व्यक्ति दो निश्चित स्थानों के बीच की दूरी a किमी/घंटा की चाल से खत्म करता है, तो t1 घंटे देर से पहुंचता है, तथा जब b किमी/घंटा की चाल से तय करता है, तब वह t2 घण्टे पहले पहुंचता है, तो दोनो स्थानों के बीच की दूरी =     ab(t1+t2)/(b-a) km
11). यदि कोई व्यक्ति a km/h की चाल से चलता है, तो वह अपनी मंजिल पर t1 घंटे लेट पहुंचता है, अगली बार वह अपनी चाल में b km/h की वृद्धि करता है, तो वह t2 घंटे लेट पहुंचता है, तब उसके द्वारा तय की गई दूरी = a(a+b)(t1-t2)/b
12). दो व्यक्ति X …