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Sat September 20, 2014  

Ans: N o space o f space 50 p comma space 25 p space a n d space 10 p space c o i n s space r a t i o space equals space 5 space : thin space 9 space : thin space 4  L e t s space a s s u m e space n u m b e r space o f space 50 p space c o i n s space a s space 5 x comma space 25 p space c o i n s space a s space 9 x space a n d space 10 p space c o i n s space a s space 4 x  T o t a l space v a l u e equals R s. space 206  5 x open parentheses 0.5 close parentheses plus 9 x open parentheses 0.25 close parentheses plus 4 x open parentheses 0.1 close parentheses equals 206  2.5 x space plus thin space 2.25 x space plus thin space 0.4 x space equals space 5.15 x equals 206  x space equals space fraction numerator 206 over denominator 5.15 end fraction equals 40 space c o i n s  S o space N u m b e r space o f space 50 p space c o i n s space a r e space 200 comma space 25 p space c o i n s space a r e space 360 space a n d space 10 p space c o i n s space a r e space 160.  T o t a l space n u m b e r space o f space c o i n s space equals space 200 space plus thin space 360 space plus thin space 160 space equals space 720 space c o i n s

Sat September 20, 2014  

Ans: T h e space L C M space o f space 16 comma space 18 comma space 24 space a n d space 30 space i s space 720. T h e space l e a s t space m u l t i p l e space o f space 720 space w h i c h space i s space o f space 5 space d i g i t s space i s space 720 cross times 14 equals space 10080. T h e r e f o r e space t h e space l e a s t space 5 space d i g i t space n u m b e r space w h i c h space i s space d i v i s i b l e space b y space 16 comma space 18 comma space 24 space a n d space 30 space i s space 10080.

Sat September 20, 2014  

Ans: Dear raisanjaysingh@rediffmail.com

Thanks for asking us a question in Ask the Expert section of TopperLearning.com.
We have not understood the query that you have posted. We would request you to clarify / provide additional details so that we may answer this to the best of the ability.

Regards

Topperlearning Team.

Sat September 20, 2014  

Ans: W e space k n o w space t h a t open parentheses a minus b close parentheses cubed equals a cubed minus 3 a squared b plus 3 a b squared minus b cubed

Fri September 19, 2014  

Ans: W e space k n o w space t h a t x cubed plus y cubed plus z cubed minus 3 x y z equals open parentheses x plus y plus z close parentheses open parentheses x squared plus y squared plus z squared minus x y minus y z minus z x close parentheses... left parenthesis 1 right parenthesis W e space n e e d space t o space e v a l u a t e comma space open parentheses 42 close parentheses cubed minus open parentheses 18 close parentheses cubed minus open parentheses 24 close parentheses cubed L e t space u s space r e w r i t e space t h e space e x p r e s s i o n space a s comma open parentheses 42 close parentheses cubed minus open parentheses 18 close parentheses cubed minus open parentheses 24 close parentheses cubed equals open parentheses 42 close parentheses cubed plus open parentheses minus 18 close parentheses cubed plus open parentheses minus 24 close parentheses cubed space A p p l y i n g space t h e space i d e n t i t y space left parenthesis 1 right parenthesis comma space w e space h a v e comma space open parentheses 42 close parentheses cubed plus open parentheses minus 18 close parentheses cubed plus open parentheses minus 24 close parentheses cubed space equals open parentheses 42 plus open parentheses minus 18 close parentheses plus open parentheses minus 24 close parentheses close parentheses open square brackets open parentheses 42 close parentheses squared plus open parentheses minus 18 close parentheses squared plus open parentheses minus 24 close parentheses squared minus open parentheses 42 close parentheses open parentheses minus 18 close parentheses minus open parentheses minus 18 close parentheses open parentheses minus 24 close parentheses minus open parentheses minus 24 close parentheses open parentheses 42 close parentheses close square brackets S i n c e space 42 minus 18 minus 24 equals 0 comma space t h e space a b o v e space e q u a t i o n space b e c o m e s space z e r o comma space a n d space h e n c e comma space w e space h a v e space open parentheses 42 close parentheses cubed plus open parentheses minus 18 close parentheses cubed plus open parentheses minus 24 close parentheses cubed space equals 0

Fri September 19, 2014  

Ans:   Though in the long form of periodic table lanthanides and actinides are placed separately below the periodic table. The real positions of these elements in the long form of periodic table is in between the d-block elements.

Fri September 19, 2014  

Ans: Metals conduct electricity because the electrons inside the metal are relatively free to move. So when electricity is through metals, electrons carry electricity and spread it all over the metal. The mobility of electrons is the reason why metals conduct electricity.

Fri September 19, 2014  

Ans: 1.  Non-metals have 5-7 electrons in their valence shell. So they have a strong tendency to gain electrons to form the stable octet configuration. So they accept electrons readily to form electronegative ions. This is the reason why non-metals are electronegative in nature. 2. All noble gases are already in a state of maximum stability and so do not enter into a chemical combination under normal conditions. Their stability is so prominent that they do not even form diatomic molecules and exist as monoatomic gaseous atoms.

Fri September 19, 2014  

Ans: Lets solve this question by taking an example.    Plot square root of 13 on number line   Draw a number line ( l ) and mark the points O, A, B and C such that OA = AB = BC = 1 Draw CD ⊥  l,  such that CD = 1 units.
Join OC
In right ΔOCD,
OD 2  = OC 2  + CD 2 OD 2  = 9 + 1 = 10 OD = square root of 10

Taking O as centre and D as radius, draw an arc which cuts  l  in F

Now, draw EF ⊥  l,  such that EF = 1 units
Join OE'
In right ΔOEF,
OE 2  = OF 2  + EF 2 OE = square root of 11

Taking O as centre and OE as radius, draw an arc which cuts  l  in H

Now, draw GH ⊥  l , such that GH = 1 units
Join OG
In right ΔOGH, OG 2  = OH 2  + GH 2 OG = square root of 12
Taking O as centre and OG as radius, draw an arc which cuts  l  in J.

Now, draw IJ ⊥  l , such that IJ = 1 units
Join OI,
In right ΔOIJ, OI 2  = OJ 2  + JI 2 OI = square root of 13= OL
Taking O as centre and OI as radius, draw an arc which cuts  l  in L.

The point L represents square root of 13on the number line.

Fri September 19, 2014  

Ans: Investment in education is one of the main sources of human capital which facilitates inventions and innovations. It increases the accessibility of people to modern and scientific ideas. It helps to gain knowledge, skills and attitude which would enable them to understand changes in society and scientific advancements. The contribution of the educated person to economic growth is more than the illiterate person. If a healthy person could provide uninterrupted labour supply for a longer period of time, then health is also an important factor for economic growth. Thus expenditure on education, health, on job training contributes to the formation of human capital in a society.

Fri September 19, 2014  

Ans: Reflex action is an automatic, quick and involuntary action in the body brought about by a stimulus. Characteristics of reflex actions: 1. Rapid automatic responses to a stimulus without the conscious involvement of the brain 2. Controlled by spinal cord 3. Very quick and instantaneous 4. May involve any muscle or a gland  5. Can be conditioned Some examples of reflex actions: 1. Shivering when it is too cold or sweating when it is too hot. 2. Non-stop beating of the heart. 3. Instant withdrawal of the hand when it accidently touches a hot iron. 4. Dilation of the pupil in eyes when looking in the dark.

Fri September 19, 2014  

Ans: Acrylic fabric  made from acrylic fibre is an example of artificial wool.

Fri September 19, 2014  

Ans: Acrylic fabric  made from acrylic fibre is an example of artificial wool.

Fri September 19, 2014  

Ans: Understanding biology would be much simpler if we are able to understand the terminologies used in biology. Difficult biology words and terms can be made easy to understand by becoming familiar with common prefixes and suffixes used in biology. These affixes, derived from Latin and Greek roots, form the basis for many difficult biology words. It would be much simpler to remember the most complex terms in biology by breaking down these terms into discrete units.
Examples: 1. Autotroph This word can be separated as follows: Auto- troph.
Auto - means self, troph - means nourish. Autotrophs are organisms capable of self-nourishment. 2. Cytokinesis
This word can be separated as follows: Cyto- kinesis.
Cyto - means cell, kinesis - means movement. Cytokinesis refers to the movement of the cytoplasm that produces individual daughter cells during cell division.

Thu September 18, 2014  

Ans: The microorganism involved in biogas production is mainly facultative and strictly anaerobic bacteria. The anaerobic  microorganism  break down biodegradable material in the absence of oxygen. They produce methane which is the major constituent of biogas.

Thu September 18, 2014  

Ans: Hi nileshpatel19752000@yahoo.com, The answer to the query that you have posted can be found in the NCERT text book for class IX. Kindly refer to the page numbers 107 and 108 for your answer.It explains all the details needed for your query.

Thu September 18, 2014  

Ans: O 2 = (σ1s) 2 (σ*1s) 2 (σ2s) 2 (σ*2s) 2 (σ2z) 2 (π2px 2 = π2py 2 ) (π*2px 1 = π*2py 1 ) Bond order = (N b -N a ) /2 = (10-6)/2= 2 It is paramagnetic as it contains two unpaired electrons. O 2 + = = (σ1s) 2 (σ*1s) 2 (σ2s) 2 (σ*2s) 2 (σ2z) 2 (π2px 2 = π2py 2 ) (π*2px 1 ) Bond order = 2.5 It is paramagnetic as it contains one unpaired electron. O 2 + = = (σ1s) 2 (σ*1s) 2 (σ2s) 2 (σ*2s) 2 (σ2z) 2 (π2px 2 = π2py 2 ) (π*2px 2 = π*2py 1 ) Bond order = 1.5 It is paramagnetic as it contains one unpaired electron.

Thu September 18, 2014  

Ans: Nuclear   fission Nuclear  fusion In fission reactions, a heavy nucleus is split into two nuclei with smaller mass numbers. In fusion reactions, two light nuclei are combined to form a heavier, more stable nucleus. High-speed neutrons are required in nuclear fission reactions. Very high temperature is required for nuclear fusion reactions The amount of energy required to split two atoms in a fission reaction is less as compared to fusion reaction. A tremendous large amount of energy is required to bring two or more protons close enough to overcome their electrostatic force of repulsion. Tremendous large amount of energy is released by fission reactions; but lower than the energy released by nuclear fusion. The energy released by fusion reactions is three to four times greater than the energy released by fission reaction. The energy produced by nuclear fission reactions is used in nuclear power plans for generation of electricity. The energy produced by fusion reaction is not controlled as far and cannot be used for generation of electricity. It is used in Sun through which energy is created.

Thu September 18, 2014  

Ans: P r i m e space f a c t o r i z a t i o n space o f space 529 space i s comma space 529 space equals space 23 space cross times space 23  square root of 529 equals square root of 23 cross times 23 end root space equals space 23

Thu September 18, 2014  

Ans: The National Assembly, under the leadership of Abbe Sieyes and Mirabeau, had resolved to draft a Constitution for France which would effectively limit the powers of the monarch. These powers, instead of being concentrated in the hands of one person, were now separated and assigned to different political institutions - the legislature, executive and judiciary. The monarchy was retained, but the king did not enjoy absolute power and authority, as he did in the days of pre-revolution France. Therefore, through the new Constitution, the leadership of the Third Estate transformed France into a constitutional monarchy.
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