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pl give me summary of ch. Sensory,attentional, and perceptual processes

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please what is the meaning of general and pricipal solution in trignometry.

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how much below the surface of the earth does the acceleration due to gravity becomes 99% of its value at the earth's surface ? (radius of earth =6400km )

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Please provide answer of physical education sample papers

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Drive the expression for viscous force acting on spherical body of radius r moving with velocity v through viscous liquid of coefficient of viscocityη Using dimensional analysis.

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Discus the variation of acceleration due to gravity with altitude . How does the expression modify when h<<R?

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Ans. Let g be the value of acceleration due to gravity at the surface of earth and g' at a height h above the surface of earth. If the earth is considered as a sphere of homogeneous composition, then g at any point on the surface of the earth is given by:
{tex}g = {GM\over R^2}{/tex} …………(1)
Where M mass of earth, R is radius of Earth.
Now, we ll determine Value of g at the distance h from the surface of earth.
Then distance b/w center of earth and point = (R+h)
{tex}g' = {GM\over (R+h)^2}{/tex} ……………(2)
divide eq (2) by (1)
{tex}{g'\over g} ={ { GM\over (R+h)^2} \over {GM\over R^2}}{/tex}
{tex}=> {g'\over g}= {R^2\over (R+h)^2}{/tex}
{tex}=> {g'\over g}= {R^2\over R^2 (1+{h\over R})^2} {/tex}
{tex}=> {g'\over g}= {1\over (1+{h\over R})^2}{/tex}
{tex}=> {g'\over g}= {(1+{h\over R})^{2}}{/tex}
Expanding using Binomial Theorem and neglecting terms with higher power of R, we get
{tex}=> {g'\over g}=(12{h\over R}){/tex}
So, The value of acceleration due to gravity 'g' decreases with altitude 'h'.
When h<< R then expression is
{tex}=> {g'\over g}=(12h){/tex}
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Drive the expression for pressure of a gas in a container? using it relate kinetic energy with pressure?

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4 cards are drawn at a time from a pack of 52 cards find the probability of getting all the 4 cards of the same suit.

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Two parallel force of magnitude 4 and 6 newton are acting on a body placed at 4m apart. Resultant force will be

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Fill in the blanks with little ,a little , the little, a few , few , the few
......... Day's rest is all that is needed.

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Ans. Few days rest is all that is needed.
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Convert 144km/ hr to m/s?

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Ans. {tex}144Km/h = {144\times 1000\over 3600} = 40m/s{/tex}
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what is syn gas and how it is prepared nowdays

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Who founded c++

check out on internet
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Bjarne stroustrup
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CHECK
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IM NOT MUCH SURE AND CONFIRM IN MY ANSWER CHECK IN INTERNET
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BJARNE STROUSTRUP .IM SURE
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Dennis Ritchie
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Carbon14 decay with a half life of about 5,800 year. In a sample of bone, the ratio of carbon14 to carbon12 is found to be 1/4 of what it is in free air. This bone may belong to period about x centuries ago, where x is

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Min. No. Of meiotic division required to produce 62 pollen grains

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In Meiotic division, each cell divides into 4 daughter cells. During pollen grain formation, pollen grain mother cell divides meiotically to proudce 4 cell tetrad that differente from each other to form 4 pollen grains. so, minium number of cell division required is 16.
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Write an article for your school magazine on the topic unfair mean no the right way

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What is green chemistry

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Ans. Green chemistry, also called sustainable chemistry, is an area of chemistry and chemical engineering focused on the designing of products and processes that minimize the use and generation of hazardous substances.
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Anything less than a complete structure of a cell does not ensure independent living. What does this statement means?

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All parts of cell have some function, independent living requires all these functions to be done accuretly. so, organisms having incomplete cellular structure will not survive.
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Name the financial statement in which the balance of suspense account will be shown

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Why we take force are equal when we connect two springs in series ?

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You are given a cylinder once the cylinder rolled up to a inclined plane and the same cylinder is rolled down the same inclined plane.
Find direction of friction in both the cases

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Ans. The direction of the frictional force will be up the inclined plane in both the motions.
The friction acts opposite to the relative motion of the point of contact on ground. In both the cases the force acting on the point of cylinder in contact with the plane is {tex}mgSin\theta{/tex}.
As there is pure rolling the velocity and acceleration of the point of contact must be zero. So friction acts upwards along the inclined plane.
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discuss the diagonal relationship between Be and Al

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Ans. The ionic radius of Be^{2+} is estimated to be 31 pm : the charge/ radius ratio is nearly the same as that of the Al^{3+ }ion. Hence beryllium resembles aluminium in some ways. Some of the similarities are:
 Like aluminum, beryllium is not readily attacked by acids because of the presence of an oxide film on the surface of the metal.
 Beryllium hydroxide dissolves in excess of alkali to give a beryllate ion, just as aluminium hydroxide gives aluminate ion.
 The chlorides of both beryllium and aluminium have Cl bridged chloride structure in vapour phase. Both the chlorides are soluble in organic solvents and are strong Lewis acids. They are used as Friedel Craft catalysts.
 Beryllium and aluminium ions have strong tendency to form complexes.
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compare the structure of water molecule and ice?

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What range of activities business comprise of

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Ans. Business include the following range of activities:
 Industry, i.e. production and related activities
 Commerce, i.e. trade and aides to trade
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What do you understand by quantitative and qualitative data?

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Ans. Quatitative data are anything that can be expressed as a number, or quantified. Examples of quantitative data are scores on achievement tests,number of hours of study, or weight of a subject. These data may berepresented by ordinal, interval or ratio scales and lend themselves to most statistical manipulation.
Qualitative data cannot be expressed as a number. Data that represent nominal scales such as gender, socieo economic status, religious preference are usually considered to be qualitative data.
Both types of data are valid types of measurement, and both are used in education journals. Only quantitative data can be analyzed statistically, and thus more rigorous assessments of the data are possible.
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