Thank You everyone who is reading my blog as my blog has reached 1100 pageviews in 1 year!!!! :)

Hi Friends,

On 2^nd October it was a national holiday for all of us and then I and my Dad decided to go to a place called Rani Ki Vav in Patan, Gujarat. This place is approximately 125 KM from Ahmedabad. We lost our way many times but at last at 10:45 am we could reach the step well. It was a really sunny day and there was a lot of hot breeze and we were enjoying the trip of the express highways of Mehsana (In Gujarat).

Rani Ki Vav is a 1000 year old step well built by Queen Udayamati in memory of her husband King Bhimadeva I of Solanki Dynasty. Oh my god! When I reached there I saw that the step well was really deep inside. The step well is a 7 storey structure in the underground which reflects the knowledge of an architect preserving and retaining water during that period.

There was a tunnel connected with this well which helped the royal family to escape during the time of war.

 Rani Ki Vav has 292 pillars supported by the pavilions of the step well. The well had the water of River Saraswati. Water was available in the well till 1988 but now it is dry. 

Nearby we went to a place called Saharalinga Tank. It was a really gigantic tank and river Saraswati used to flow over there. It is believed that Akbar’s tutor was killed there. 

Thanks!

Ruchit Nambiar :) 

Hi Friends,

Today I am going to share something interesting with you all.When I  entered the school we saw that every single child was wishing every teacher Happy Teacher's Day and giving them a card or a rose. Grade 12 had done a Performance which was Spectacular. We had planned for 1 week and at last we finished all our planning. We had planned it with grades 3,4 5 and 6 that we will do something special for our teachers. All of us had done something or the other and on the last day we got out final product together. Grade 7 (which is my grade) did a fashion show. We gave each and every teacher a goodie bag and a certificate which had 1 dialogue that would represent the teacher. In the goodie bag we had a rainbowloom band and a card which had quills on them. At the end of the day Grade 6 had organized a food party for all the teachers where the teachers had a feast. It was a small day but I enjoyed it a lot. 

Thank You 

Ruchit Nambiar

Hi Friends,

I had gone to my grandmother's house on 16/7/2014 and I reached on 20/7/2014. In these 4 days I had gone to a resort named Samara Gardens. Wowwww.......  it was a really beautiful place. Wow the way the home were designed it was really good. I also met my sister Kyra who had come after a long time from London. She is 3 years old and she is really cute. In the resort half of the time I spent playing with her and half of the time I spent swimming. After our visit to Samara Gardens we went to Nariman Point, Gateway of India and we saw Antilla, Mukesh Ambani's house. Wowwwwww...... the design of the house was so good that I felt like staying in his house forever, but unfortunately we are not allowed to go inside. After going there we went to a place called Haji Ali juice center where we ate icecream. The next day I had to go back to my home . 

At Last Our home is HOME SWEET HOME! :)

For all the FIFA Fans this is a site

fifa.com

Here you will get to know the match schedules and timings of the matches.

Hi Friends,

I know it has been a long time since I posted. Today I am going to share with you about the first day of my school. My school started on 12th June 2014 and the first thing we had was a class meet up where we met our new teachers Maulik Sir and Priti ma'am. We introduced ourselves to our teachers and by this they got to know us better. After this grades 3,4,5,6 and 7 met up and we got to know who was new. Then ..... we had a anchor game. A anchor game is a game which sets the tone for the year. My class's anchor game's name was The Cardboard Block. Wow its a really huge name, now let me tell you what happens in it.

Instructions:-

You will get cardboard's and you have to choose your own path and you have to reach a destination. A leader will lead you to your destination by putting cardboard pieces on your path. The last person of the group has to collect all the cardboard's and pass it to the next person, and beware!!! if your leg goes out of the cardboard piece then you will have to start the whole game again. 

My class was divided into 2 groups and we had to follow the instructions as shown above. My group had people who stepped out of the cardboard many times, but slowly we started having trust on each other and at last we reached our destination!! :) When people were stepping out of the cardboard I thought that our group wouldn't win the game but when we worked as a team we did it.

And this was the end of my day. I hope I could have more but because it was a half day our school got over so early.

Thank You 

Ruchit Nambiar

Hi Friends,

Today I am going to share a story about our great leader M.K Gandhi. The Story starts:-

When Gandhi was studying law at the University College Of London, there was a professor, whose last name was Peters, who felt animosity for Gandhi, and because Gandhi never lowered his head towards him, their “arguments” were very common.

One day, Mr. Peters was having lunch at the dining room of the University and Gandhi came along with his tray and sat next to the Professor. The Professor, in his arrogance, said, “Mr. Gandhi: you do not understand… a pig and a bird do not sit together to eat”, to which Gandhi replies, “You do not worry Professor, I’ll fly away”, and he went and sat at another table.

Mr. Peters, green of rage, decides to take revenge on the next test, but Gandhi responds brilliantly to all questions. Then Mr. Peters asked him the following question, “Mr. Gandhi, if you are walking down the street and find a package, and with it there is a bag of wisdom and another bag with a lot of money; which one will you take?

Without hesitating, Gandhi responded, “the one with the money, of course.

Me Peters, smiling said, “I, in your place, would have taken the wisdom,

Don’t you think?

“Each one take what one doesn’t have”, responded Gandhi indifferently.

Mr. Peters, already hysteric, writes on the exam sheet the word “idiot” and gives it to Gandhi. Gandhi takes the exam sheet and says, “Mr. Peters, you singed the sheet but you did not give me the grade.”

Bye Friends hope to meet you again,

Ruchit Nambiar

Dear friends,

We had gone to Gandhi Ashram and we saw many things which Gandhiji had used when he was alive.  We saw many things and did a reflection on what did we see and learn. We saw many things which Gandhiji used. We saw what he did and his history in detail.  

Movie on Gandhi- I saw a film on M.K Gandhi and in that film I saw that they showed Gandhi and what all did he do for the nation. They also showed the events that took in Gandhi’s life. They taught me many things about truth, principles of life and upholding the principles. It even taught me the simple life of Gandhiji and meaningful and purposeful life. Self-reliance and concerned about the poor.

My Life Is My Message “Mahatma Gandhi"

Mohandas Karamchand Gandhi was born on October 2 1869 in Porbandar, Gujarat, India.  His father’s name was Karamchand Gandhi and his mother's name was Putlibai. Gandhi married Kasturba at the age of 13. Gandhi was raised in a Hindu family and his father was a merchant. He was trained law at Inner Temple in London. M.K Gandhi first tried civil disobedience in South Africa. In South Africa apartheid was prevalent. When he came in India in 1915 he saw farmers, peasants and urban laborers against Land Tax and Discrimination. That time the Britishers were ruling in India.

In 1921 he started a party called the Indian National Congress and led a nationwide campaign for poverty, women’s rights and ending untouchability. Gandhi led Indians to challenge the British rule of Salt Tax and he walled 400 Kms and this was called the Dandi March. He was imprisoned for many years in South Africa and India. Gandhi practiced non-violence and truth in all situations and told other people the same thing. He wove his own clothes and wore the Traditional Dhoti and a shawl spun on a Charkha. He was a strict and disciplined vegetarian.

Gandhi was very sad and painful when a section of the people demanding for division of India on the basis of religion, the policy adopted by the Britishers. On August 15 1947 the Britisher's left India. Gandhiji was assassinated by Pandit Nathuram Godse on 30th January 1948. This day is called Martyr's Day. His last words were He Ram, He Ram. 

As a class we had gone to Gandhi Ashram and we went to see what Gandhi did in his early life. We saw his Charkha and the place where he used to sit at home with Mirabai. I also got to know a message from Gandhi he wrote “My life is my Message”

I understood  Gandhi’s life is  upholding of  truth,  non-violence, ahimsa,  simple life, meaningful and purposeful life!

I feel, every citizens of the country especially leaders, scholars, educationists, social reformers should visit Gandhi ashram, Ahmedabad.

I would like to know how  Gandhian philosophy has influenced you in your personal and professional life?

Please post your comments.

Every Year we have a programme named Artist In Residence. In this programme we have a artist who comes with a Talent and teaches that to us. This year's artist was Mr Hrishikesh Pawar. He is a contemporary Dancer. We had our show on 8th February and the play went a hit. We had a Tech rehearsal on 7th February and Kiran Ma'am told us that the play and the dance for both the groups were very good. 

We were happy with the feedback and we also got to know that the Sponsorship Committee had got 2,45,000 and we were very happy too. Our play was based o a book named Jonathan Livingston Seagull and that book told us that whatever happens in life you should follow your dreams.

 The grade 3&4 play was about a story from Design For Change and how the children get a change in a girl named Kamla who is Physically challenged and how her friends help her to go to school. On the final day we got a standing ovation and all the parents told us that the play and the job done by all the committee's was very good.



Regards
Ruchit Uday Nambiar

 

Dear Friends,

Every week a group from our school goes to Prabhat. Prabhat is a NGO(Non Governmental Organization) where there are Cerebral Palsy and Mental Retardation kids. Mental Retardation means when the child doesn't act like his/her age and Cerebral Palsy means a condition marked by impaired muscle coordination or other disabilities, typically caused by damage to the brain before or at birth.  We are focusing on 5 main kids of Prabhat and making a documentary on them.

 Our first draft was seen on Monday that was 17/2/14 and our second draft still has to be made. First when I went to Prabhat I was feeling scared a lot because the children would not act normal. After a lot of interactions I started enjoying with them and including them in a group. My group is focusing on a boy named Shalman. He is a boy who has 75.5% Mental Retardation. He is 14 years old. His parents told us that he has improved a lot. He used to throw stones at others and would not eat anything nor  listen to anybody. Now he has started to listen and interact with all the kids of Prabhat and he is not  aggressive as he was.

Do not exclude physically challenged or Mentally Challenged Kids. After this please take a pledge that I will not try to exclude Physically or Mentally Challenged Kids. I would be happy if you do so.

I invite all the comments & a few questions

Is it not our responsibility to take care of these kids and spread smiles on their face?

If not then who will take care of these children !!!

Inviting your valuable feedback's

To get to know more about Prabhat please go on this site- 

http://www.prabhatedu.org/

Regards

Ruchit Nambiar

For All The Barclays Premier League Fan's this is a site

http://www.premierleague.com/

Manchester City manager Manuel Pellegrini risks a UEFA sanction after launching a scathing attack on the match referee after his side's 2-0 loss to Barcelona in the Champions League.

Barcelona took charge of the last 16 tie thanks to a second-half penalty from Lionel Messi and a late Dani Alves strike at the Etihad Stadium in Tuesday's first leg, and Pellegrini blamed match official Jonas Eriksson for his side's defeat.

In a wide-ranging attack, Pellegrini accused Eriksson of making two mistakes over the penalty decision and even questioned why a Swedish official had been given control of the game.

He also said that Eriksson should not have been in charge because he had been criticised by Barcelona following his performance in their 0-0 draw at AC Milan in the quarter-finals of the 2011-12 competition.

Eriksson sent off City defender Martin Demichelis for bringing down Messi in the incident that yielded the 54th-minute penalty and Pellegrini said: "I think that the referee decided the game.

"Before the penalty there was the foul on (Jesus) Navas, when he (Eriksson) was three metres from the player, so he saw it without any problem.

"From the beginning I felt that the referee was not impartial to both teams. The penalty on Martin Demichelis was not a penalty - it was outside the box."

Asked why he had spoken to Eriksson at the final whistle, Pellegrini replied: "Just to tell him that he had decided the game. He must be very happy, because he decided the game."

The Chilean added: "He didn't have any control of the game. He decided for Barcelona from the beginning until the end.

"I think it was not a good idea to put a referee from Sweden in such an important match and a referee that made such important mistakes against Barcelona (in an earlier match)."

When he was asked to explain his reservations about Eriksson's nationality, Pellegrini said: "I think there are more important football (nations) than Sweden in Europe.

"It was a big game with two important teams. I think maybe in that kind of game, you need a referee with more experience.

"I think the best (biggest) mistake was to put a referee that damaged Barcelona in the stage of group (sic).

"This referee whistled the Barcelona-Milan game and he made an important error against Barcelona. Today he arranged (atoned for it)."

With Pellegrini preoccupied by his gripes about Eriksson's performance, it was left to captain Vincent Kompany to vow that City had not given up on the tie.

"If the tempo was in this game, it would have been to our advantage," he told ITV.

"If the game is the same as today, and we manage to stay away from some fouls, we have got a chance."

Barcelona manager Gerardo Martino felt that the outcome of the game was "fair", but he warned against complacency ahead of the second leg at Camp Nou on March 12.

"I'm not necessarily confident (about going through), but it's true that we've done a good game in the away leg," he said.

"We just have to repeat the same performance."

Media focus prior to the game had centred on the extent to which Barcelona have lost their mantle in the light of their 7-0 demolition by eventual champions Bayern Munich in last season's semi-finals.

Chelsea manager Jose Mourinho described Martino's side "as the worst Barcelona of many, many years" and Barca midfielder Cesc Fabregas said that he and his team-mates were pleased to have silenced their critics.

"We had a point to prove, and we did it very well," he told ITV.

"Some people were talking a bit too much before the game and now they have to shut up for a few days."

MATCH REPORT

Barcelona took control of their Champions League round of 16 tie against 10-man Manchester City on Tuesday when they won 2-0 at the Etihad Stadium thanks to a Lionel Messi penalty and a late strike from Dani Alves.

Messi, tripped by Martin Demichelis on the edge of the box, which earned the defender a red card, scored after 54 minutes to give the four-time European champions the lead over City, who were playing in the knockout rounds for the first time.

Alves scored in stoppage time when he shot through the legs of City goalkeeper Joe Hart after a marauding run down the right.

The visitors dominated the opening 20 minutes and finished far stronger against City, who seemed overawed by the occasion.

The two sides, who had scored 228 goals between them this season, failed to produce the goalfest that many expected.

The two away goals Barcelona did score have given them a huge advantage going into the second leg on March 12.

FULL TIME

Man City 0 Barca 2 (Messi 54", Alves 90")

Two second half goals from Lionel Messi and Dani Alves gave Barcelona a 2-0 victory over Manchester City in the first leg of the Champions League Round of 16 fixture at the Etihad Stadium on Tuesday night.

After a drab and lacklustre goalless first half the match came to life immediately in the second session with Messi putting the Catalan side in front in the 54th minute from a penalty after he was tripped in the City box when in a position to score.

Alves almost sealed their berth in the quarters in the 90th minute for Gerardo Martino's side who will play the second leg match at the Nou Camp on March 12.

The defeat will leave Manuel Pellegrini a lot of thinking to do as his side failed to impress in front of a packed crowd.

Except for a few close calls they hardly gave Valdes under the Barcelona goal much cause for concern.

The best chance they had was when David Silva sent his crashing right footer to the right of Valdes but the goalkeeper was equal to the task bringing off a brilliant save.

90" GOAL! Alves scores after a defensive lapse from City.

85" City trying their best to find the equaliser but Valdes makes another good save.

84" Valdes makes a timely save after Dzeko from an offside position tries to score.

80" Barcelona come up with a superb move leaving the City defenders rooted but Fabregas is off-side denying Pique a goal.

76" Brilliant save by Valdes to deny Silva a certain goal. This was by far City's best shot at the Barca goal.

75" YELLOW! Macherano is booked.

73" Neymar comes in for Sanchez to a loud cheer.

72" Barca start to toy with City who are defending with 10 men.

67" Alves on his own this time but misses target by inches after Hart is stretched.

66" Overlapping Alves once again crosses but Xavi send his floater well over the crosspiece.

63" Dani Alves has a shy at the City goal but his low shot is easily collected by Hart.

61" From the counter Nasri and Negredo threaten the Barca citadel but Pique and Mascherano rise up to the challenge.

60" Pique earns a free-kick just outside the City box but Hart jumps over the crowd to punch it away.

57" Nasri makes his way in.

Man City 0 Barcelona 1 (Messi 54')

54" GOAL! Messi scores sending Hart the wrong way.

53" RED CARD! Demichelis trips Messi in box. It's a penalty.

49" Messi and Fabregas move into the City area but the defence does well to get the ball to away.

46" No changes made by either side at the break.

Manchester City will be happy to have kept Barcelona quiet in the first 45 minutes of play at the Etihad Stadium although it must have been disappointing for those who expected a goal fest.

HALF TIME

Man City 0 Barcelona 0

43" Negredo once again fails to make good a cross as he heads wide.

42" Iniesta to Messi, makes one of his darting runs through the middle and relays for Fabregas but his cross is cleared to safety.

40" With five minutes to go for the half time whistle, the crowd is getting impatient.

38" Sanchez makes a solo run but is nicely challenged by Demichelis.

36" YELLOW! for Kolarov for a foul on Alves.

35" Mascherano sends a long diagonal ball but Negredo's half-hearted effort is futile.

33" Free-kick for Barca after Messi is tackled wrongly by Kompany but the Barca talisman can only thump the resulting freekick into the City wall.

32" Xavi's long range shot tests Hart who collects it on the second attempt.

30" Messi tries a top-of-the-box shot with his weaker foot, his right, and the ball soars high over the bar.

29" Iniesta cuts through the City defence like knife through butter but lack finish and ideas in front of goal.

27" YELLOW! for Negredo for a tackle on Pique.

26" Negredo has a feeble attempt at the Barca goal but Valdes makes a regulation collection.

25" Both teams having an equal share of the exchanges now.

24" City earn another free-kick and from a goalmouth melee Valdes fumbles in his first attempt to collect but does so in his second before Toure can get to it.

YELLOW! Dani Alves is booked for a second rough tackle.

23" City come into their own slowly as they get more of the ball possession.

19" Silva plays in Negredo who makes a wonderful attempt from a tight angle.

18" Kolarov made a dangerous run beating a defender but his angle is narrowed by Valdes. he manages to chip across but there are no takers.

16" City get into the Barca box but Valdes is felled by Kolarov while going for a header.

15" City struggle to come up with a single decent move.

12" Barca get another corner but Hart is quick to charge out and punch it away.

10" Barca dominate early play but are yet to make any headway.

9" Messi, Iniesta and Sanchez try to break through but the City defence looks solid.

7" Messi to Busquest good one-two but Toure stands firm.

5" Barca take early control amid a lot of cheer for City

3" Barca earn their first corner taken by Xavi but defended well by City who then go on to launch an attack of their own.

1" Play gets under way with City kicking off.

Neymar is on the Barcelona bench tonight, and the Brazilian superstar has admitted he is surprised just how good Lionel Messi is since joining the club in the summer.

"He surprised me a lot!" said Neymar. "Even as a player. Watching him on TV back home, I hadn't realised just how good he was."

In five minutes' time, we'll get to see for ourselves. Excited?

Time to get charged up for the most anticipated match of the Champions League as the players start trooping in. All eyes are on Messi.

Messi gives a thumbs up as he is applauded by City fans either side of the tunnel as he walks after warming up.

Pellegrini's record in Champions League as coach reads like this: 50 matches, 22 wins, 9 lost and 19 draws.

Tension is palpable at the Etihad Stadium as just 15 minutes to go for the kick-off between two teams meeting in the Champions League for the first time.

Deafening cries of 'Barca, Barca, Barca' greet the Barcelona players as they emerge for their warm-up.

Plenty of travelling fans still outside Etihad Stadium but the ones inside are making a right racket.

There is a cracking atmosphere at the Etihad ahead of the round of 16 first leg tie between Manchester city and Barcelona.

Manuel Pellegrini makes six changes to the City starting XI from the one that kicked off the win over Chelsea, with Aleksandar Kolarov set to start on the left side of midfield ahead of Gael Clichy at left-back.

Fernandinho returns from injury but along with Pablo Zabaleta is a booking away from a one-game ban, while James Milner is suspended.

There are three changes for Barcelona from the side that thrashed Rayo Vallecano 6-0 on Saturday, but Neymar only makes the bench.

Fabregas gets look-in as Neymar is benched.

STARTING XI

Man City: Hart; Zabaleta, Kompany, Demichelis, Clichy; Navas, Toure, Fernandinho, Kolarov; Silva; Negredo.
Subs: Pantilimon, Lescott, Richards, Garcia, Nasri, Jovetic, Dzeko

Barcelona: Valdes, Alba, Pique, Mascherano, Alves, Xavi, Busquets, Iniesta, Fabregas, Messi, Sanchez.
Subs: Pinto, Bartra, Adriano, Song, Sergi Roberto, Pedro and Neymar Jr.

TEAM NEWS

Neymar is unlikely to start despite a good comeback from injury in the match against Rayo.

STAT ATTACK
Barcelona are winless in five straight games in England.

Man City are undefeated at home against Spanish clubs.

Barcelona have attempted (4,812) and completed more passes (4,125) than any side in this season's competition.
Lionel Messi (65 goals) is only six goals away from equalling Raul's Champions League goalscoring record (71 goals). He's netted six goals in only three games this season.

Manchester City have never failed to score at home in the Champions League.

In the group stages, Barcelona topped Group H with 13 points, while City finished on 15 points along with Bayern Munich but had to settle for second place behind the German side on goal difference.

Manuel Pelledrini's side partake in their first last-16 Champions League tie.

PREVIEW

It can be billed as the 'clash of the titans' when Manchester City take on four-times European champions Barcerlona in the first leg of the Champions League round of 16 fixture at the Etihad Stadium in a few hours from now.

Going by performances in their respective leagues - City are third in the Premier League with 54 points, while Barca are on top of La Liga with 60 points - there is no doubt that these two teams should have met in the final of Europe's premier tournament.

But such is the nature of the draw that one team will have to bow out before even making the last eight stage thus depriving their myriad fans a chance to back them all the way to the pinnacle of European success.

Barca coach Gerardo Martino was right when he said: "City are one of the best teams in the world and it is difficult for us to be playing them now when they are in such a good level. This could easily have been the final, and if we had to play them I would have preferred to play them later."

However, Lionel Messi's return to the side should give Martino and his boys the confidence to take on Manuel Pellegrini's side in their own den.

The maverick Argentinian scored twice against Rayo Vallecano on Saturday to overtake Alfredo di Stefano in La Liga scoring history.

The star striker has now scored 337 goals for Barcelona, a record for one club, but his record in England is in stark contrast having only ever managed one goal in the 2011 Champions League final against Manchester United at Wembley.

Barcelona can however fall back on Neymar who too was out of action for a couple of weeks and the coach said he was delighted Neymar was 'healthy again'.

For City, the return of Samir Nasri after he missed seven games due to injury, will come as a boost. Nasri came on as substitute and scored the second goal against Chelsea in the FA Cup over the weekend.

But the men in blue have cause for worry with Sergio Aguero being ruled out of the first leg through injury, while James Milner misses the tie due to suspension.

Pablo Zabaleta and Fernandinho too need to avoid rough tackles as they could miss the second leg if booked here.

Coach Pellegrini is unperturbed though with a side that has scored 117 goals in all competitions this season.

His only aim is to get a good result against a good side. "Our fans deserve a victory against a big club to show how the club is progressing," said the former Villareal, Malaga and Real Madrid coach.

City gave a hint of their growing strength with a 3-2 win away to champions Bayern Munich to bring about a transformation from domestic also-rans to European champions.

If they can come out on top in the two-leg clash against a great side like Barcelona it would mean as good as winning the title.

Yesterday's Barcelona Vs Manchester City's Score

Some more information- http://www.premierleague.com/en-gb/news/news/2013-14/feb/champions-league-review-190214.html


Barcelona Rocks

Hi All,

To All the Viewers of this blog,

I am Ruchit Nambiar from Grade 6 The Riverside School, Ahmedabad, Gujarat, India and I have made this blog for everybody to explore through this blog and get to know some science & some Math. I have just started creating blogs and this is my first blog. I love Technology a lot although I am not a expert at it I love exploring new things in my Galaxy Tab 2. I even like to go through some new sites like study sites and refer through subjects.

If anybody has a question please mail it to me at ruchitnambiar.nambiar18@gmail.com


Regards

Ruchit Uday Nambiar

This is some information on Light & Eye


As mentioned in the first section of Lesson 2, our eyes are sensitive to a very narrow band of frequencies within the enormous range of frequencies of the electromagnetic spectrum. This narrow band of frequencies is referred to as the visible light spectrum. Visible light - that which is detectable by the human eye - consists of wavelengths ranging from approximately 780 nanometer (7.80 x 10^-7 m) down to 390 nanometer (3.90 x 10^-7 m). Specific wavelengths within the spectrum correspond to a specific color based upon how humans typically perceive light of that wavelength. The long wavelength end of the spectrum corresponds to light that is perceived by humans to be red and the short wavelength end of the spectrum corresponds to light that is perceived to be violet. Other colors within the spectrum include orange, yellow, green and blue. The graphic below depicts the approximate range of wavelengths that are associated with the various perceived colors within the spectrum.


Color Cones
Color can be thought of as a psychological and physiological response to light waves of a specific frequency or set of frequencies impinging upon the eye. An understanding of the human response to color demands that one understand the biology of the eye. Light that enters the eye through the pupil ultimately strikes the inside surface of the eye known as the retina. The retina is lined with a variety of light sensing cells known as rods and cones. While the rods on the retina are sensitive to the intensity of light, they cannot distinguish between lights of different wavelengths. On the other hand, the cones are the color-sensing cells of the retina. When light of a given wavelength enters the eye and strikes the cones of the retina, a chemical reaction is activated that results in an electrical impulse being sent along nerves to the brain. It is believed that there are three kinds of cones, each sensitive to its own range of wavelengths within the visible light spectrum. These three kinds of cones are referred to as red cones, green cones, and blue cones because of their respective sensitivity to the wavelengths of light that are associated with red, green and blue. Since the red cone is sensitive to a range of wavelengths, it is not only activated by wavelengths of red light, but also (to a lesser extent) by wavelengths of orange light, yellow light and even green light. In the same manner, the green cone is most sensitive to wavelengths of light associated with the color green. Yet the green cone can also be activated by wavelengths of light associated with the colors yellow and blue. The graphic below is a sensitivity curve that depicts the range of wavelengths and the sensitivity level for the three kinds of cones.
The cone sensitivity curve shown above helps us to better understand our response to the light that is incident upon the retina. While the response is activated by the physics of light waves, the response itself is both physiological and psychological. Suppose that white light - i.e., light consisting of the full range of wavelengths within the visible light spectrum - is incident upon the retina. Upon striking the retina, the physiological occurs: photochemical reactions occur within the cones to produce electrical impulses that are sent along nerves to the brain. The cones respond to the incident light by sending a message forward to brain, saying, "Light is hitting me." Upon reaching the brain, the psychological occurs: the brain detects the electrical messages being sent by the cones and interprets the meaning of the messages. The brain responds by saying "it is white." For the case of white light entering the eye and striking the retina, each of the three kinds of cones would be activated into sending the electrical messages along to the brain. And the brain recognizes that the messages are being sent by all three cones and somehow interprets this to mean that white light has entered the eye.
Now suppose that light in the yellow range of wavelengths (approximately 577 nm to 597 nm) enters the eye and strikes the retina. Light with these wavelengths would activate both the green and the red cones of the retina. Upon striking the retina, the physiological occurs: electrical messages are sent by both the red and the green cones to the brain. Once received by the brain, the psychological occurs: the brain recognizes that the light has activated both the red and the green cones and somehow interprets this to mean that the object is yellow. In this sense, the yellow appearance of objects is simply the result of yellow light from the object entering our eye and stimulating the red and the green cones simultaneously.
If the appearance of yellow is perceived of an object when it activates the red and the green cones simultaneously, then what appearance would result if two overlapping red and green spotlights entered our eye? Using the same three-cone theory, we could make some predictions of the result. Red light entering our eye would mostly activate the red color cone; and green light entering our eye would mostly activate the green color cone. Each cone would send their usual electrical messages to the brain. If the brain has been psychologically trained to interpret these two signals to mean "yellow", then the brain would perceive the overlapping red and green spotlights to appear as yellow. To the eye-brain system, there is no difference in the physiological and psychological response to yellow light and a mixing of red and green light. The brain has no means of distinguishing between the two physical situations.

In a technical sense, it is really not appropriate to refer to light as being colored. Light is simply a wave with a specific wavelength or a mixture of wavelengths; it has no color in and of itself. An object that is emitting or reflecting light to our eye appears to have a specific color as the result of the eye-brain response to the wavelength. So technically, there is really no such thing as yellow light. Rather, there is light with a wavelength of about 590 nm that appears yellow. And there is also light with a mixture of wavelengths of about 700 nm and 530 nm that together appears yellow. The yellow appearance of these two clearly different light sources can be traced to the physiological and psychological response of the eye-brain system, and not to the light itself. So to be technically appropriate, a person would refer to "yellow light" as "light that creates a yellow appearance." Yet, to maintain a larger collection of friendships, a person would refer to "yellow light" as "yellow light."
In the next several sections of Lesson 2, we will explore these concepts further by introducing three primary colors of light and generating some simple rules for predicting the color appearance of objects in terms of the three primary colors.


Thanks
Ruchit Nambiar
Grade 6
Riverside School