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Why structural isomerism is not possible for propane?

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Show that T_{1 }, T_{2 }, T_{3 }, .... T_{n }.... form an AP where T_{n }is defined as: T_{n }= 9  5n. Also find the sum of the first 15 terms.

We have to prove something also

Please read the question carefully.. Question also says that Show that T1 , T2 , T3 , .... Tn .... form an AP where Tn is defined as: Tn = 9  5n
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Just calculate the 1st 3 or 4 terms & show the constant common difference.
T_{1} = 9  5 = 4
T_{2 }= 9  10 = 1
T_{3} = 9  15 = 6
T_{4 } = 9  20 = 11
Now, if one checks the difference in any of the consecutive terms, it is 5 which is constant number.
Also, T_{n} = 9  5n (given) => T_{n1} = 9  5(n  1)
Further, T_{n }  T_{n1 } = (9  5n)  {9  5(n  1)}
= 9  5n  (9  5n + 5) = 9  5n  9 + 5n  5 =  5 (Common Difference between any 2 consecutive terms for any value of n)
Hence, one can say that it is forming an AP.
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Given: T_{n} = 9  5n
T_{1} = a = 9  5 x 1 = 9  5 = 4
T_{2} = 9  5 x 2 = 9  10 = 1
Therefore, d = 1  4 = 5
S_{15} = n/2[2a + (n  1)d]
= 15/2[2 x 4 + (15  1) x (5)]
= 15/2[8  70]
= 15/2 x [62]
= 465
Therefore, the sum of 15 terms of given AP is 465.
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If the ratio of sum of the first n terms of an a.p is m^{2 }: n^{2}, show that the ratio of its m^{th }and nth term is (2m1 ) : (2n1)....

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Ans. Let First Term of AP = a
Common Difference = d
Then
\(S_m = {m\over 2} [{2a+(m1)d}]\)
And
\(S_n = {n\over 2} [{2a+(n1)d}]\)
=> \({S_m\over S_n} = { m^2\over n^2}\)
=> \({2m [2a+(m1)d] \over 2n[2a+(n1)d]} = {m^2\over n^2}\)
=> \({ [2a+(m1)d] \over [2a+(n1)d]} = {m\over n}\)
=> \( 2an+mnd  nd = 2am+ mnd md\)
=> \( 2an2am = nd md\)
=> \( 2a(nm) = (n m)d\)
=> 2a = d ......(1)
=> \({a_m\over a_n} ={ a+(m1)d \over a+(n1)d}\)
=> \({a_m\over a_n} ={ a+(m1)2a\over a+(n1)2a}\)
=> \({a_m\over a_n} ={ 2m1\over 2n1}\)
Hence Proved
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If f_{1 }and f_{2} are focal length of two lens,what is the relation for equivalent focal length?

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If angle of incidence=90, then angle of refraction=?

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To answer this, one must know the mediums of incidence & refraction. then the below formula can be used:
<i>n1 * sin A = n2 * sin B</i>
where A is the angle of Incidence & B is the angle of Refration. Also, n1 is the index of refraction for the material the incident light ray is traveling through, and n2 is the index of refraction for the material the refracted light ray is traveling through.
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Acc. To snells law n_{21 x}n_{12}=?

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Acc. To snells law n_{21 x}n_{12}= 1 (Answer)
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Formula of vinyl chloride?

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And. C_{2}H_{3}Cl
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Homologous organ ?

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The organs which perform different functions in different species but have similar basic structure and similar embryonic origin are called homologous organs.
For eg  1. Forelimbs of frog, lizard, humans, birds, etc.
2. Radish and carrot
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The arm of a human, the wing of a bird or a bat, the leg of a dog and the flipper of a dolphin or whale are homologous structures. They are different and have a different purpose, but they are similar and share common traits.
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What is a covalent bond?

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The sharing of electrons by an atom to complete its electronic configuration leads to the formation of covalent bonds. Example carbon forms covalent bonds.
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A circuit has fuse of 5A. What us the maximum number of 100W bulbs that can be safely used in circuit?

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Suppose x number of such bulbs can be used
Power of one bulb = 100 watt
Power of x bulbs (p) = 100 X x watts
Potential difference (V) = 220 volts
I = 5 ampere
We know that P = VI
100 X x = 220 x 5
x = 220 x 5 /100 = 11 bulbs.Thanks (0)
For an AP Sm=20 and Sn=10 and nm=1,then prove that n=10÷a where a=d.

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\(I \space think \space in \space question S_m = 10 \space and \space S_n = 20 \)
Ans. Given : \(S_m = 10 \)
\(S_n = 20 \space \space \space \space ..... (1) \)
=> nm = 1
=> m = n1
The sum of m terms i.e (n1) terms
\(S_{n1} =S_m = 10 \space \space \space \space \space \space ...... (2) \)
=> \(n^{th} term = S_n  S_{n1}\)
=>\(n^{th} term = 20  10 = 10\)
=> \(a + (n1)d = 10\)
=> \(a + (n1)a = 10 \space \space \space \space \space [as \space a =d ] \)
=> \(a+ na a = 10 \)
=> \(na = 10 \)
=> \(n = {10\over a}\)
Hence proved
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How to improve my minor mistake in maths.

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Work without tension. Enjoy doing maths. Never think it as meri attma hamesha satayegee. Best of luck.
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Practice maths for 3 hours daily with full concentration
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Blind spot

Please give some reference!!
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Ans.The blind spot is the area on the retina without receptors that respond to light. Therefore an image that falls on this region will NOT be seen. It is in this region that the optic nerve exits the eye on its way to the brain.
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A three times magnified image of a candle flame is to be projected on a wall which type of lens required for this purpose if the candle is at a distance of 6m from the wall calculate the focal length of the lens

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m = v/u
3 = 6/u
u = 2
By lens formula
1/u  1/v = 1/f
1/2  1/6 = 1/f
3  2/6 = 1/f
1/6 = 1/f
f = 6 cm
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naubat khane Mein Ibadat part May Sandesh likhiye

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Write causes of Bolivian water War?

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 Bolivia is a poor country.The UN forced it's government to give up its control over water supplies
 The rights over water supply was sold to an MNC by government for a city of Cochabamba.The MNC increased the price of water
 Most of the people got the bill of about Rs1000 and there average income of people is Rs 5000.Thus this led to simultaneous revolt by people.This led to Bolivian Water War
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Which enzyme helps in breaking surcose into glucose and fructose?

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The enzyme sucrase digests sucrose or table sugar into its constituent units of glucose and fructose, while lactase breaks lactose or milk sugar into glucose and galactose. These monosaccharides are absorbed in the small intestine and transported to the liver through blood.
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Invertase
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The radii of circular ends of a bucket are 5.5 cm and 15.5 cm and its height is 24 cm. Find the surface area of the bucket.

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Slant height (l) = {h^{2} + (R  r)^{2})}^{1/2}
= {24^{2} + (15.5  5.5)^{2} }^{1/2}
= {576 + 100}^{1/2}
= 26 cm
CSA of bucket = πl(R + r) + πr^{2}
= 22/7{26(15.5 + 5.5) + (5.5)^{2}}
= 22/7{30.25 + 546}
= 22/7 × 576.35
= 1811.07 sq. cm
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Q)What is the difference between regeneration and fragmentation?

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Fragmentation
Regeneration
1. Fragmentation occurs in multicellular organisms with simple body organisation.
1. Regeneration occurs in fully differentiated multicellular organisms with complex body organization.
2. In fragmentation, an organism breaks into pieces and each piece develops into new individual.
2. In regeneration organisms if breaks into pieces, each piece may or may not develop into new individual.
3. No specialised cells are involved in fragmentation.
3. In regeneration, specialised cells proliferate and form a mass of cells. The cells from the mass differentiate to form different cells types and tissues.
Example: Spirogyra
Example: Regeneration of blood cells in mammals.
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For external boards will our sa1 result affect our sa2 result for the final cgpa? Sa1 marks will be added to our sa2 marks to get the final cgpa??

So then if I got a cgpa of 8.6 in the first term can I get a 10cgpa in the final result?
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Yes , sa 1 is important .
If you want to get good cgpa then you have tobringo
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what was the composition of agent orange poison?

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Ans. It was a 50/50 mixture of two herbicides: 2,4D and 2,4,5T
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Write a letter to principal to issue a library book until the exam

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The perimeter of a sector of a circle of radius 5.2 cm is 16.4 cm.find the area of a circle.

Please check your question. If radius is already given then you can find the area easily.
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The sum of the number and its reciprocal is 2 ×1/30.find the number

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Coal on burning prodces heat and energy but when we eat it then we dont get energy,but we eat an apple then we will get energy.why?

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Because our bile is not so strong that it can digest coal and get energy from it. Also coal has no glucose and we take glucose as energy.
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what is 8/15 of an hour ( in minutes )

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8/15 of an hour
= 8/15 of 60 min
= 8/15 × 16 min
= 8 × 4 min
= 32 minutes
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32minuts
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why human eye is able to see the 3d objects ?

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Human eye is able to see the 3D objets due to double eyes that can see objects with two differnet angles.
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why rainbow is curve?

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Rainbow is curved as horizon appears curved and dispesed light enters the eyes after total internal reflection.
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If 3+5+7+........ to n terms/ 5+8+11+.........to 10 terms = 7. Find 'n' ?

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Both the numerator and denominator are the sums of two series up to 'n' terms:
Since the sum = (n/2)(2a+(n1)d)
For series in the numerator :
a=3, d=2, n=n
Therefore numerator = (n/2)*(6+(n1)2) = (n/2)*(2n+4)
And for the denominator series:
a=5, d=3, n=10
Therefore denominator = (10/2)*(10+(101)3) = (n/2)*(3n+7) = 185
Therefore Acc. to question:
(n/2)*(2n+4) / (185) = 7
= n^{2} +2n 1295 = 0
= n^{2} + 37n  35n  1295 = 0
=n=35 ( Since ncan not be equal to 37)
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"Punishment does catch up with the sinner although it may be delayed
sometimes‘.
Comment on this statement with the reference to the poem the rime of the ancient mariner.

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i dont know
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