The arrangement of the system should be in parallel.
We can prove it with the help of formula
1/R= 1/R1 + 1/R2
1/R = 1/2 +1/2
1/R = 1
R= 1 Ohm

R₁ = R₂ = R₃ = 3 Ω

1/R = 1/R₁ + 1/R₂ + 1/R₃

= 1/3 + 1/3 + 1/3 = 3/3 = 1

∴ R = 1 Ω

The chemical bond formed by the sharing of an electron pair between two atoms so that both the atoms get their octet complete is called covalent bond. The molecules formed as a result of sharing of electron between two atoms are called as covalent molecules

ABCD is a trapezium with AB || DC, E and F are points on non-parallel sides AD and BC respectively such that EF is parallel to AB show that 

Given trap. ABCD in which AB || DC and EF || AB.
To prove:    
Const: Join A-C.
Proof: ∵ AB || DC and EF || AB
⇒    AB || EF || DC
Now, in ∆ADC, we have
                       
                       ...(i)
[using Basic proportionality theorem]

Now, in ∆ABC, we have
                     
                       ...(ii)
Comparing (i) and (ii), we get

Fire - greed, avarice, lust, conflict and fury.

Ice - cruelty, intolerance, rigidity, insensitivity, coldness, indifference and hatred.
'Fire' stands for greed, avarice, lust, conflict and fury. 'Ice' stands for cruelty, intolerance, rigidity, insensitivity, coldness, indifference and hatred.

According to the law of combination of resistance in parallel, the reciprocal of the combined resistance of a number of resistances connected in parallel is equal to the sum of the reciprocals of all the individual resistances.

If five resistances are connected in series and all are of 0.2 ohm then their resistances would be added.

As per the law of combination of resistances in series,

R = R₁ +  R₂ +  R₃ + R₄ + R₅

R = 0.2 + 0.2 + 0.2 + 0.2 + 0.2 = 1ohm

We have,

2x + 3y = 11 ….(1)

2x – 4y = – 24 ….(2)

From (1), we have 2x = 11 – 3y

Substituting 2x = 11 – 3y in (2), we get

11 – 3y – 4y = –24

⇒ –7y = – 24 – 11

⇒ –7y = – 35

⇒ y = 5

Putting y = 5 in (1), we get

2x + 3 × 5 = 11

2x = 11 – 15

⇒ x = –4/2 = – 2

Hence, x = – 2 and y = 5

Again putting x = – 2 and y = 5 in y = mx + 3, we get

5x = m(–2) + 3

⇒ –2m = 5 – 3

⇒ m = – 1

According to the law of combination of resistances in series, the combined resistance of any number of resistances connected in series is equal to the sum of the individual resistances.

Mirror Formula

The distance of an object on principal axis from pole of spherical mirror is called object distance(u).

The distance of position of image on principal axis from pole of spherical mirror is called image distance(v).

  1       1        1

—- + —- = —-

 u        v         f

Carbon has four electron in its valence shell orbital. So, it can neither accept nor gain four electron. One way to complete octet is by sharing of electrons. So, carbon forms covalent bond to complete its octet.

About the author - Vallikannan is pseudonym of R.S Krishnasamy’s. He is an Indian Tamil writer, journalist, critic, translator.

Theme of the story - Through Valli in Madam Rides the Bus,  Vallikannan depicts the curious nature of the children. The story also shows that how easily children are fascinated by new things and their curiosity doesn’t end without them experiencing the delights of fantasy life in their life. Just as we see Valli has a desire to go on a bus ride and she manages to go all alone. The experience of her first bus ride has been depicted by Vallikannan in a humorous and rambling way. Through the story, we get to see the world from the perspective of a child.

Phosphorus has valency 3.

The valence (or valency) of an element is a measure of its combining power with other atoms when it forms chemical compounds or molecules.
In PH3​,  P is combined to 3 H atoms, so the valency of phosphorous is +3.

The number of valence electrons or the number of electrons in the outermost shell of phosphorus is 3. - Thus, one atom of phosphorus is capable of combining with three atoms of hydrogen in order to form phosphine (PH3). Therefore, the valency of phosphorus in PH3 is +3.

Three examples to show the contribution of culture to the growth of nationalism in Europe were:

•  Romanticism was a European cultural movement aimed at developing national unity by creating a sense of shared heritage and common history. The Romantic artists' emphasis on emotions, intuition and mystical feelings gave shape and expression to nationalist sentiments. The strength of art in promoting nationalism is well exemplified in the role played by European poets and artists in mobilising public opinion to support the Greeks in their struggle to establish their national identity.
•  Folk songs, dances and poetry contributed to popularising the spirit of nationalism and patriotic fervour in Europe. Collecting and recording the different forms of folk culture was important for building a national consciousness. Being a part of the lives of the common people, folk culture enabled nationalists to carry the message of nationalism to a large and diverse audience. The Polish composer Karol Kurpinski celebrated and popularised the Polish nationalist struggle through his operas and music, turning folk dances like the polonaise and mazurka into nationalist symbols.
• Language also played a distinctive role in developing nationalist feelings in Europe. An example of this is how during Russian occupation, the use of Polish came to be seen as a symbol of struggle against Russian dominance. During this period, Polish language was forced out of schools and Russian language was imposed everywhere. Following the defeat of an armed rebellion against Russian rule in 1831, many members of the clergy in Poland began using language as a weapon of national resistance. They did so by refusing to preach in Russian, and by using Polish for Church gatherings and religious instruction. The emphasis on the use of vernacular language, the language of the masses, helped spread the message of national unity.