Test Papers – ICSE – Class – X
ICSE Grade X Biology Demo Videos
Now friends and let us talk about the Interesting phenomenon termed as parturition or childbirth so first of all we see parturition also means childbirth The full term of the development of an In embryo in the uterus is called as gestation Now in humans it lasts For about 280 days As we already know And at the time of birth The baby is pushed out Why the powerful contraction Of the muscles Of the uterus And these powerful contractions Of the muscles of the uterus are caused due to a hormone That is Oxytocin Which is released by the Posterior Lobe of the Pituitary gland and when the child is coming out It is giving out its head first So whenever the child is getting born The first stage which occurs is the head Stage During which the head of the baby Is given out through the vagina Now after this we see friends That in a few minutes When the baby is taken out The blood vessels in the Umbilical cord Will be getting shrunken and when the blood vessels Get shrunk they can be tied and cut After about 15 minutes The placenta brakes from the Uterus And is expelled out As after birth Uterus contracts and gradually comes back to normal in a few days now the new one which is born Will be announcing Its arrival by letting out a sharp cry And this cry of the baby Is nature’s cleansing process The clearing process Of the baby’s Respiratory Passage Now friends after this We shall be taking a look At a very beautiful video Which will be making it more clear About the process of childbirth or vaginal birth Thank you so much Let us look at the video first Before we end up with this module during a normal vaginal childbirth the first stage of labour last for about 12 hours to 19 hours and it starts when the baby settles lower in the pelvis in response the cervix begins to face or become thinner and dilate all widen then the amniotic sac ruptures giving out a mucoid fluid the cervix dilation is brought about due to a hormone termed as relaxin which is released by the placenta disc the cervix fully dilates and the baby’s head moves towards the opening of the cervix ya when the baby’s head is moving out of the cervix the upper half of the uterus actively contracts and for this contraction we have a hormone responsible which is Oxytocin this hormone is released by the posterior pituitary gland which is also known as neurohypofisys the lower half of the uterus remains relaxed to push the baby outwards in a normal virginal birth the head of the baby moves outwards first thus it is the head first stage so head moves out through the vagina which is also known as the birth canal once the head moves out completely the body moves out by passing the shoulders one by one once the baby is out after a few minutes the umbilical cord is cut and due to further contractions of the uterus the placenta which is there is given out of the uterus as an after birth thus completing the childbirth once the child is out the child gives out its first cry this cry as we know is very much necessary for the opening of the respiratory passages of the child thank you.
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CBSE X English Demo videos
Hi, students, I am Ratnali Sharma, and we are going to start with one incredible poem today that is The Snake, okay, and the writer of this poem is D.H. Lawrence, alright. Now let us know a little about the poem. The Snake is one of Lawrence’s most famous poems. In this poem Lawrence tells of a confrontation with a snake he had at his water trough. This poem is actually based on an incident that occurred to him and obviously reflects his feelings and emotions. Lawrence was honoured by the snake’s presence but was also afraid. Throughout the poem, Lawrence illustrates his point about the strife and the clash of the opposites.
Education and social conventions make Lawrence think that the poisonous snake must be killed and that a brave man should undertake the task. For a brief moment, Lawrence lacked the faith of his own intuition and missed his chance with one of the lords of life. The poem is written in free verse and is an excellent representative of modernist literature.
Now let us have a little look at the background of the poet, that is David Herbert Richards Lawrence and he lived between 1885 and 1930. He was an English novelist, poet, playwright, essayist and literary critic. His collected work represents the dehumanizing effect of modernity and industrialization. The poem Snake was composed in 1923 and forms part of Reptiles section of Lawrence’s poetic collection called ‘Birds, Beasts and Flowers’.
Now let us start with the poem. The first part:
A snake came to my water trough
On a hot, hot day, and I in pyjamas for the heat,
To drink there.
Now see, in the first line there is this word ‘trough’ what does it mean, a long narrow open container for animals to eat or drink out of. So over here the snake had come to the poet’s water trough on a hot, hot day. And the writer, ‘I’ over here is the writer in his pyjamas, ‘pyjamas’ a loose jacket and pants worn in bed, okay. So on one hot morning or afternoon, this particular day when the writer poet came to the water trough, he saw a snake.
Now this poem begins with D.H. Lawrence narrating an encounter he had with a snake. It was a hot day when the poet in his pyjamas was going to fill his pitcher with water as the heat was unbearable. He noticed that a snake was ahead of him and it had come to drink water from the trough.
Alright, now:
In the deep strange-scented shade of the great dark carab tree
I came down the steps with my pitcher
And must wait, must stand and wait, for there was at the trough before me.
Over here, the word, ‘scented’ means having a strong pleasant smell. And ‘carab tree’ a red flowered evergreen common to Mediterranean area, okay, and a ‘pitcher’ is a large jug in which you fill water.
The poet came towards the water trough near the carab tree which had a strange scent. He had to stand and wait at his own water trough because the snake was already there before him.
With this we are done with our first module, thank you.
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CBSE X Economics Demo Videos
Hello, students, welcome to the beautiful world of economics with our beautiful lesson – Globalization and the Indian Economy. So let us begin with this lesson.
Dear students, we all know that in 1947 India achieved independence. This lesson is all about India’s journeys from 1947 to this day, wow, and in this journey we shall briefly halt in the year 1991. India before 1991 was a black and white country, and India after 1991 is a colourful and vibrant country. What led to this transformation?
Before we understand all about this, first let us visit the early 20th century world, and find out what the world economy was then. During the early 20th century, production was largely organized within the countries. What this meant was countries like USA and Europe concentrated on the production of machinery and technology. Countries like Brazil specialized in the production of coffee, South Africa was well known for its gold and diamonds. Australia well known for its dairy products, and India specialized in the production of agro based commodities.
Most countries were closed economies, this means these economies had minimum trade relation with the outside world. So we had limited imports and limited exports, except for essential goods we kept our contact with the rest of the world to a bare minimum. Trade was the main channel connecting the distant countries. Colonies like India which were under the British rule exported raw materials and food stuffs and imported finished goods.
Then came India’s independence and the post independent stage. After independence India adopted the mixed economy. In mixed economy the public and the private sector co-exist. The public sector is owned and run by the government. The private sector is owned and managed by the private individuals. The strategic and basic industries were controlled by the public sector, for example, industries like the defence and telecommunication, the railways. The other industries were controlled by the private sector. The private sector was not allowed in the industries reserved with the public sector. Also the government protected its own industries from the private sector and the foreign investment feeling that these industries were more into the profit motive than the welfare of the people. The public sector in the meantime was in dire needs of additional capital as well as modern technology. Most public sector companies needed to increase their profit margins.
Then in 1991 came the critical financial situation of India. From 1947 to 1991, India’s import bills were very high and our export earnings were very low. Our imports majorly consisted of oil from the Middle East countries. And another big import was machinery and technology from USA and Europe. Our exports consisted of raw materials and food grains. Before 1991 our biggest export partner was USSR. But post 1991, USSR disintegrated into Russia and 14 different countries. So our export earnings fell.
In 1990, Iraq invaded Kuwait for the control on oil wells. In 1991 US began an aerial raid to drive back the Iraqi troops. Our primary sellers, Iraq, Kuwait and USA were at war with each other. And this definitely impacted the Indian economy because our oil bills escalated. By January 1991 our forex reserves were only at $1.2 billion and this depleted to half by June. Our forex was barely enough to last roughly for three weeks of essential imports.
Dear students, summing up India’s economy in the pre 1991 era. Number one, we had losses in the public sector companies. We had restrictions on the private sector as well as on foreign trade as well as restrictions on foreign investments. Also we had a problem of low forex reserves. India approached the World Bank to bail us out. And we asked the World Bank for a loan. The World Bank agreed but on the condition that India open up her markets for foreign trade and foreign investment. And India agreed to open up for foreign trade as well as foreign investments, and how did we do this. In 1991 July 24, the government of India introduced the new economic policy keeping in mind three objectives. The objective number one was L, the second objective was P and the third objective was G. L stands for Liberalization, P stands for privatization and G stands for Globalization.
In the coming modules of the lesson we shall understand each one of them beautifully.
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CBSE X Geography Demo Videos
Hello, students, in this module we will learn about the distribution of minerals in India.
India is fortunate to have fairly rich and varied mineral resources. So, we have minerals resources found in large quantities and as well as that we have variety of minerals found in our country of India. However, the distribution of these minerals is not even. Rather it is much more uneven distribution in our country. Broadly speaking the Peninsular rocks contains maximum reserves of mineral deposits like coal, metallic mineral, mica and many other non-metallic minerals. So, out of all the major sub divisions of India, the Peninsular plateau region of India has maximum mineral deposits.
Let’s look at distribution in our country. The sedimentary rocks on the western and the eastern flanks of India that is the western part and the eastern part of India, especially, the states of Gujarat and Assam have most of the petroleum deposits. If you look at Rajasthan it has a rock system similar to the Peninsular region and that is why this region has large reserves of non-ferrous minerals. If you look at the North Indian plains, the dark green area which is shown in the map, this region is called as alluvial plains of India. The vast alluvial plains of North India are almost devoid of economic minerals. It means this entire region has very limited distribution of important minerals. These variations exist largely because of the differences in the geological structure of all these various regions, the processes and the time involved in the formation of minerals.
Let us now study the distribution of a few major minerals in India. But before we do that, we need to always remember that the concentration of minerals in the ore, the ease of extraction of the minerals and the closeness to the market plays a very important role in affecting economical viability that is the affordability of the reserve. Thus, to meet the demand, a choice has to be made between the number of possible options. When that choice is made, when it is done, a mineral deposit or a reserve turns into a mine.
Now, let us concentrate on very first on the ferrous minerals that is the minerals containing iron. Ferrous minerals accounts for about 3/4th of the total value of production of metallic minerals in our country of India. They provide a strong base for the development of metallurgical industries. India exports substantial quantities of ferrous minerals after meeting her internal demands. So, we will learn about the very first ferrous minerals that is iron ore in the next module, thank you.
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CBSE X Mathematics Demo Videos
Hello, students let us go through the next word problem based on Sn formula.
The sum is – 200 logs are stacked in the following manner, 20 logs in the bottom row, 19 in the next row, 18 in the next and so on. In how many rows are the 200 logs placed and how many logs are in the top row? Let’s go step by step. Let’s try to understand what is given. Log of woods something which you already know this is how it looks like. How are they placed, please understand. 20 logs are in the bottom row, right, so in the bottom row, in the first row, the first term there are 20 logs, right. In the second row there are 19, in the third row there are 18. So, a1 is 20, a2 is 19, a3 is 18. So here n represents the rows, first row n is equal to 1, second row n is equal to 2, third row n is equal to 3. And the terms are the number of logs, right. The question is how many rows, means find the total number of terms. So, we are supposed to find the value of n. A total of 200 logs are placed. How many rows are the 200 logs placed, so we are suppose to find the value of n, because number of rows means number of terms that is we are supposed to find the value of n, clear. So, we need to find the value of n as I said the number of rows and for that what is given to us, Sn is equal to 200 because the total 200 logs are placed, clear. The AP formed is 20, 19, 18 and so on as we discussed. These numbers form an AP with a is equal to 20, d is equal to 19 minus 20 which is equal to minus 1, right. And the total number of logs as we said is 200, so we know that Sn is equal to 200, very, very simple, right. Now, let’s solve. How do we solve? The total number of logs is equal to Sn is equal to 200. Sn is known to us, A is known to us, d is known to us. You are supposed to find n? How do we do it, we use the formula. What’s the formula, Sn is equal to n upon 2 into 2a plus n minus 1 into d, why we are using this formula, because d is known to us, right. Lets substitute, 200 is equal to n upon 2 into 2 into 20 plus n minus 1 into minus 1. Let’s move ahead, take 2 to the other side, it will get multiplied by 200. We get 200 into 2 is equal to n into 40 minus 1 into n is minus n and minus 1 into minus 1 is plus 1. Let’s move on, 200 into 2 is 400, n into 40 plus 1 is 41 minus n. So, 400 is equal to again open the bracket we get n into 41 that’s 41n and n into n is minus n square. Again we are getting a quadratic equation, let us solve it by the method of factorisation but before that write all the terms on one side. So, that there is zero on the other side. So, minus n square goes there, it becomes plus n square, 41n goes there becomes minus 41n and 400 remains there, so it is plus 400 is equal to zero. Let’s solve this quadratic equation by factorisation method. What is factorisation method? We need the factors of 400 which on adding gives us minus 41, why which on adding because 400 has got a plus sign, right. So, 400 factors which on adding gives us minus 41. Lets factorise 400, how do we do it, 2 into 2 into 2 into 2 into 5 into 5. What is the rule that we followed to find the factors, the biggest together and the smallest together, right. So 2 into 2 into 2 into 2 together that is 16, 5 into 5 together that is 25. Now 25 and 16, will it give 41 on adding. Yes, 25 plus 16 is 41 but then we want minus 41, so you want minus 16 and minus 25 because minus 25 and minus 16 is minus 41. So, let’s factorise it, n square minus 25n minus 16n plus 400 is equal to zero. Let’s take the common thing out n into n minus 25 minus 16. Because minus 16 is common the sign will change inside the bracket. So, inside the bracket, you will get n minus 25 and not plus 25, right, is equal to zero. Let’s move further, you get n minus 25 into n minus 16 is equal to zero. You get n minus 25 is equal to zero or you get n minus 16 is equal to zero, therefore n is equal to 25 or n is equal to 16. Here we are getting both the values of n as positive, now which one to chose and which one to leave. To decide that what we will do is, we will substitute n is equal to 25. We will substitute n is equal to 25 that is the number of logs, in the 25th row, in a25 because with a25, a represents number of logs in a particular row, right. So, a25 is number of logs in the 25th row. So, let’s find the number of logs in the 25th row, a25 is plus 24d, right which is equal to 20 plus 24 into minus 1, right, which is 20 minus 24 which is equal to minus 4. When we take n is equal to 25, we get number of logs in that 25th row as minus 4. But can number of logs be negative. The number of logs cannot be negative, right, minus 4 logs not possible. Since the number of logs cannot be negative, n is not equal to 25. So, what is n equal? N is equal to 16. Now, let’s find the number of logs in the 16th row. That is we are supposed to find a16 because a represents the number of logs in the 16th row, right. Let’s find a16 it’s a plus 15d that’s 20 plus 15 into minus 1, that’s 20 minus 15 which is equal to 5. So, the number of logs in the 16th row, where 16th is the top row because total number of rows are 16. So, a16 becomes the number of logs in the top row that is the 16th row, right. So, number of logs in the 16th row that is the top row is 5. So, the question is how many rows are there? There are 16 rows and how many logs are there in the top that is in the 16th row, that is a16 which equal to 5, very, very simple, right.
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CBSE X Science Demo Videos
Hello, students my name is Seema and I will be taking for you the chapter called as Periodic Classification of Elements. Now, in this chapter we will study the introduction and the need for classification. So, let’s get started.
Now, let me just give you a scenario, wherein you are going for shopping for the clothes of course. Would you like to shop for the clothes from place number 1 or from place number 2? Think and tell me which of the two will it be? Now, for me the answer will be 2. And you think why? Reason is quite simple, in the place number 2, I find that there is a systematic arrangement of clothes that have been done. So, my shopping becomes very easy. Now, you might have realised these days in the shopping centre the clothes over there, they are arranged according to the brand and in each and every brand the clothes they are further arranged according to the sizes and they are also arranged according to the colour. So, I can pick that one particular size, one particular brand and one particular coloured clothes that easily. And my task is done.
And now let us try to change the scenario and let us say this time you are going for the shopping of books and not clothes. Now, would you like to shop for your books from place number 1 or from place number 2? Again think deeply and tell which of the two it will be? For me again the answer remains the place number 1. And you think why? Reason is still the same in place number 1, I find that there is a systematic arrangement of books that have been done. So, it becomes very easy for me to pick that one book. Why, because you might have noticed that nowadays in modern libraries the books over there are arranged as per the genres, they are arranged according to the name of the author and even the name of the author they are arranged in alphabetical manner. So, it becomes quite easy to pick that one book. But you might be wondering that in chemistry why am I relating to systematic arrangements again and again. The reason for this will be unfolded in a short while.
Now, if you are talking about chemistry the most fundamental matter in chemistry is known as the ‘elements’. So, what exactly are these elements? An element is defined as a type of matter which is composed of only one kind of substance. Now how are we relating the systematic arrangement and the element? Let us look further, initially various scientists, they discovered various elements like gold. There was this element like silver, carbon, sulphur, iron and copper. These are few of the elements. And these elements based on properties they were classified as either being metals or being non-metals. For example, if I talk about element like copper, silver and iron, they are called as metals whereas carbon is called as non-metal. If it’s the element gold, it is definitely a metal and sulphur would become a non-metal. But what about element like silicon? Silicon and some other elements which showed the properties of both the metals as well as non-metals and they were known as metalloids. But this brings us to the conclusion that not all elements are metal or non-metal. Some of the elements can be metalloids as well. So, scientists came to the realisation that you know, we need a proper arrangement, a proper classification of elements, a proper study of elements.
Now, in nature as of now, if I am supposed to say, there are total of 119 elements, some of which you can see it over here. Now these 119 elements showed various properties, different properties and their understanding was also very important. That is why there was a need of systematic classification and arrangement of these elements in order to make their study easy. And this is what we are going to study in this chapter that is Periodic Classification. So, let us move ahead, let’s study efforts of classification in this chapter called as Periodic Classification of Elements.
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