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Catalogs Discussion Forums -> Mechanics -> Rotational motion -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

 Can you tell me the concept of backward spinning???

Catalogs Discussion Forums -> Differential Calculus -> Trace the curve: y^2(x^2-4)=x^4 -> Go to message
This Post 10 points    (Olaaa!! Perrrfect answer.   in 2 votes )   [?]

y2(x2 - 4) = x4

or, y2 = x4 / (x2 - 4)

or, y = + x2 / (x2 - 4)1/2

So, for the function to be defined, x2 - 4 > 0

or, x2 >4

or, x>2 and x<-2

Also,

So, you can check in which interval the function increases and decreases.

The graph would be this:

Catalogs Discussion Forums -> Physical Chemistry -> how to find electonegativity of metal by pauling method -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

http://www.tutorvista.com/chemistry/electronegativity-table

Refer this link......

Catalogs Discussion Forums -> Mechanics -> can anyone please suggest a good book to study rotational motion to clear concepts? -> Go to message
This Post 7 points    (Olaaa!! Perrrfect answer.   in 2 votes )   [?]

Rotational Mechanics by Er. Anurag Mishra. It is the best book to clear concepts related to rotational motion.

Catalogs Discussion Forums -> Analytical Geometry -> iiiiiiiimmmmmmmmmppppppp 3-; x^2 +2 root.2xy +2y^2 +4x +4 root2y +1=0 ; the dist. between thease lin -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

Given equation is x2 + 2(2)1/2 xy + 2y2 + 4x + 4(2)1/2 y + 1 = 0

 

Comparing it with general equation of second degree i.e.

 

ax2 + 2hxy + by2 + 2gx + 2fy + c = 0

 

we have a = 1, h = (2)1/2, b = 2, g = 2, f = 2(2)1/2 and c = 1.

 

It this equation represents pair of two straight parallel lines then,

 

h2 - ab = 0

 

So, (2) - (1)(2) = 0

 

So, the given lines represent straight parallel lines.

 

Now, the distance between them(d) is given by

 

d = 2 ((g2 - ac) / a(a + b))1/2 = 2 ((4 - 1)/(1)(1 + 2))1/2 = 2(1) = 2 units (Ans).........

 

Catalogs Discussion Forums -> Analytical Geometry -> Is x axis and y axis is perpendicular or not because we know condition of perpendicular is m1m2=-1 b -> Go to message
This Post 9 points    (Olaaa!! Perrrfect answer.   in 3 votes )   [?]

Two lines are perpendicular if the product of their slopes is -1 or one has a slope of 0 (a horizontal line) and the other has an undefined slope (a vertical line).

Refer: http://en.wikipedia.org/wiki/Slope

Catalogs Discussion Forums -> Optics -> LASER -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

Discuss various components of laser and explain its working taking into account terms like stimulated emission, optical inversion, photon multiplication and cavity oscillations.

Catalogs Discussion Forums -> Electricity -> BIPIN DUBEY SIR PLEASE HELP ME -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

Catalogs Discussion Forums -> Inorganic Chemistry -> diagonal relationship in periodic table -> Go to message
This Post 10 points    (Olaaa!! Perrrfect answer.   in 2 votes )   [?]

Diagonal relationship exists between certain pairs of diagonally adjacent elements in the second and third periods of the periodic table.

These pairs (Li & Mg, Be & Al, B & Si etc.) exhibit similar properties.

REASON -

Such a relationship occurs because crossing and descending the periodic table have opposing effects. On moving across a period of the periodic table, the size of the atoms decreases, and on moving down a group the size of the atoms increases. Similarly, on moving across the period, the elements become progressively more covalent, less basic and more electronegative, whereas on moving down the group the elements become more ionic, more basic and less electronegative. Thus, on both descending a group and crossing by one element the changes "cancel" each other out, and elements with similar properties which have similar chemistry are often found - the atomic size, electronegativity, properties of compounds (and so forth) of the diagonal members are similar

Catalogs Discussion Forums -> Physical Chemistry -> on uncertainity principle -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

UNCERTAINTY PRINCIPLE

In quantum mechanics, the Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot simultaneously be known to arbitrary precision.

(delta x) . (delta p) > h / 4 pi

or, (delta x) . (m) (delta v) > h / 4 pi

or, (delta x) . (delta v) > h / 4 m pi

So, for a massless particle, say photon, m = 0

So, (delta x) . (delta v) > infinity

 

@sahell, photon is massless.

@canorous i hope you have got the point.

Nudge me if you still have any doubt regarding this.

Catalogs Discussion Forums -> Trignometry -> plzz ....prove that :tan3A-tan4A-tanA = tan3A tan2A tanA -> Go to message
This Post 12 points    (Olaaa!! Perrrfect answer.   in 3 votes )   [?]

tan(3A) = tan(2A + A) =(  tan(2A) + tan(A) ) / ( 1 - tan(2A) tan(A) )

tan(3A) - tan(A) tan(2A) tan(3A) = tan(2A) + tan(A)

tan(3A) - tan(2A) - tan(A) = tan(A) tan(2A) tan(3A)

 

I think there's some problem in the question. Its not 4A but 2A.

Catalogs Discussion Forums -> Trignometry -> graph of sin of inverseof sin -> Go to message
This Post 0 points    (Olaaa!! Perrrfect answer.   in 0 votes )   [?]

f(x) = sin(sin-1x)

or, f(x) = x

So, the graph is a straight line passing through origin and inclined at an angle of pi/4 from X-axis.

Catalogs Discussion Forums -> Differential Calculus -> evalute 1/n^100 lim as r tends to infinity find summation ( r goes from 1 to n ) ( r^99) -> Go to message
This Post 15 points    (Olaaa!! Perrrfect answer.   in 3 votes )   [?]

Ans is 1/100..........

Catalogs Discussion Forums -> Mechanics -> a ball is projected vertically upwards with an initial velocity of 100m/s.find the speed of the ball -> Go to message
This Post 5 points    (Olaaa!! Perrrfect answer.   in 1 votes )   [?]

The ball will reach maximum height (h) when velocity of ball is zero.

Using, ( 0 )2 - u2 = 2 ( -g ) h

So,  h  = u2 / 2 g = ( 100 )2 / 2 g

So, velocity of ball at half the max. height ( h / 2 ) will be given by,

v2 - u2 = 2 ( - g ) ( h / 2 )

or, v2 = ( 100 )2 - ( 100 )2 / 2

or, v = 100 ( 1 / 2 )1/2 = 50 ( 2 )1/2   (Ans)............

Catalogs Discussion Forums -> Vectors -> Inequality -> Go to message
This Post 30 points    (Olaaa!! Perrrfect answer.   in 6 votes )   [?]

Catalogs Discussion Forums -> Differential Calculus -> f(x) = Ix-1I + Ix-2I , -> Go to message
This Post 30 points    (Olaaa!! Perrrfect answer.   in 6 votes )   [?]

f(x) = |x - 1| + |x - 2|

      = 2x - 3 , x > 2

               1   , 1 < x < 2

        - 2x + 3 , x < 1

Clearly, range of f(x) is [1,5].

 

Catalogs Discussion Forums -> Differential Calculus -> how to find domain and range of modulus function -> Go to message
This Post 35 points    (Olaaa!! Perrrfect answer.   in 7 votes )   [?]

f(x) = |x| is the modulus function.

 

or, f(x) = x , x > 0

               0 , x = 0

              -x . x < 0

 

Clearly now x can take any real value, so domain of function is all real values.

Now for any real x, f(x) is always positive so range of f(x) is [0,infinity).

 

It is quite clear from graph of modulus function also. ( See Below )

 

 

 

Catalogs Discussion Forums -> Analytical Geometry -> Find the values of x; y for which x^2 + y^2 takes the minimum value where (x + 5)^2 + (y-12)^2 = 14 -> Go to message
This Post 30 points    (Olaaa!! Perrrfect answer.   in 6 votes )   [?]

Using triangular inequality,

So, minimum ( x2 + y2 ) = 1

Solving the equaitons now, you'll get

x = 5 / 13 and y = - 12 / 13

Catalogs Discussion Forums -> Algebra -> let c be a fixed real number. show that a root of the equation x(x+1)(x+2).....(x+2009)=c ca -> Go to message
This Post 30 points    (Olaaa!! Perrrfect answer.   in 6 votes )   [?]

If an equation f(x) = c has a root x = a of multiplicity 2 then f'(a) = 0. If the root has multiplicity greater than 2, then also f"(a) = 0.

As, x(x + 1)(x + 2) .............. (x + 2009) = c

Taking log on both sides,

 

sum_{n=0}^{2009}ln(x+n) = ln c

 

Let f(x) = sum_{n=0}^{2009}ln(x+n).

 

or, f'(x) = sum_{n=0}^{2009}rac1{x+n}

 

 

Also, f''(x) = -sum_{n=0}^{2009}rac1{(x+n)^2}

 

Since all the terms in the sum have the same sign, it's clear that their sum cannot be zero.

 

So f(x) = ln c has no roots of multiplicity greater than 2.



To find the number of roots of multiplicity 2, note that the derivative of a function has a root between each pair of consecutive roots of the function. Since x(x+1)(x+2)...(x+2009) = 0 has 2010 roots, its derivative will have 2009 roots.

Catalogs Discussion Forums -> Integral Calculus -> good q -> Go to message
This Post 40 points    (Olaaa!! Perrrfect answer.   in 8 votes )   [?]

I = int ( (1 + cos4x) / (cotx + sinx) ) . dx

I = 2 int ( (cos22x) ( - sinx) / (cos2x - cosx  - 1) ) . dx

Put y = cosx

so, dy = - sinx . dx

Now, I = 2 int ( (2y2 -1)2 / ( y2 - y - 1 ) . dy

I = 2 int ( (4y2)(y2 - -y - 1 + y) + 1) / ( y2 - y -1 ) ) . dy

I = 8 int y2 . dy + 8 int ( y3 / ( y2 - y - 1 ) ) . dy + 2 int ( 1 / ( y2 - y - 1 ) ) . dy

I = 8 int y2 . dy + 8 int ( 2y + 1 / ( y2 - y - 1 ) ) . dy + 8 int (y + 1) . dy+ 2 int ( 1 / ( y2 - y - 1 ) ) . dy

I = 8 int y2 . dy + 8 int ( 2y - 1 / ( y2 - y - 1 ) ) . dy + 2 int ( 1 / ( y2 - y - 1 ) ) . dy + 8 int (y + 1) . dy+ 2 int ( 1 / ( y2 - y - 1 ) ) . dy

Now, you can integrate. If you still have any problem nudge me.

 

 
 
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