Test Papers – ICSE – Class – X
ICSE Grade IX Physics Demo Videos
Hello students we’re going to learn a new concept today that is we’re going to understand what is distance and what is displacement and what is the difference between this concept of distance and displacement so to understand this concept of distance and displacement let’s take a simple example we of course have a racing track as you can see and in this racing track A is the initial point and of course there’s a final point that is B so you can see the flags and these flags indicate the final point of this racing track So A is the initial point B is the final point of course there’s a car and this car is moving along this racing track so let’s make this car move this car is going to go around the racing track of course it’s going to go from the initial to the final position that is from A to B now what exactly has happened this car has gone from A to B which means it has covered the path. the path covered is indicated by the green line and you can see that the car is covering a path of 250 meters between a and B so the Green Line is indicating the path covered and it is equal to 250 meters but obviously if this was not a racing track if it was you walking along it then of course you will not go around the racing track you would just walk on the grass and go from A to B which means that the distance between A to B can be covered by another path in this case of course the car went around the racing track so we say that this is the actual path covered by the car so the actual path covered by the car is called distance the car went from a to be around the track and therefore 250 meters in this case is counted as the distance but of course like i said if you had to walk from A to B you would just walk over the glass directly from A to B so the shortest distance between a to b is not around the track but straight to be that is hundred meters so the shortest distance between the initial and the final point is hundred meters and that exactly is displacement .displacement is the shortest distance between initial and final points so you see what is distance and what displacement let’s take another example again we have the racing track we again have the car but this time the car is going to go from a to a .it’s going to take a lap around this racing track so it’s going to start from a and of course after sometime it comes back to A. remember what was distance. distance was the part covered by an object so the part covered by this object is of course the green line around the racing track so what is the distance the distance in this case is 500 meters because the part covered by the car is 500 meters so we say distance is 500 meters but what about displacement the shortest distance between the initial and final point is 0 because the initial point and the final point is the same that is point a so the shortest distance between the initial and final point zero which means my displacement is 0 which means in this case even though the distance was not zero the displacement was zero so let’s write down and recap what we saw and the car goes from a to b the distance was 250 meters but the displacement was straight down that’s hundred meters but when the car went from a to a the distance was 500 meters and the displacement was simply 0 also note that the distance is always greater than the displacement and the distance will never be zero as long as the initial and the final points are not the same so that means the distance can never be less than displacement and distance is always greater than or equal to displacement so let’s write down how to represent this displacement, displacement we know is a vector because it has a magnitude in a direction how do you represent displacement it is represented by a straight line with an arrow using a convenience scale if I want to represent a 40-metre displacement towards the east so I’m just going to make a straight line PQ you can see there’s an arrow at q so it’s a straight line it has a arrow and this has to represent forty meter displacement towards the east of course I’ve drawn this line towards the east how will you make it represent 40 meters you simply say one centimeter is 10 meters so using one centimeter is representing 10 meters of course you can draw a 40-metre line to represent this displacement exactly what is happening P is the original or the initial position Q of course the final position and then we draw this line remember the length of the straight line gives you magnitude of the displacement and therefore in this case since the magnitude of the displacement is 40 Meter I will draw four centimeter line because one centimeter represents 10 meters so 4 centimeters gives me 40 meters so simply represent displacement you draw a straight line and you see that the length gives you the magnitude of the displacement finally let’s see what’s the distinguish between distance and displacement distance of course we know is the actual part followed by a body between the points in which it moves displacement is the shortest distance between the initial and final points of the movement distance is a scalar quantity while displacement is a vector quantity Scaler of course we know has only magnitude and no Direction displacement is a vector with both magnitude and direction the third point is that distance is either equal to or greater than displacement we saw this in the racing track example displacement however it is either equal to or less than distance the fourth point is that distance is the length of the part Traversed by the object in a certain time well as displacement is the distance by the object in a specified direction remember it’s a vector so specific direction is important again it is in a certain limit that is it should be the shortest distance it depends on the part followed by the object where as this depends on only the initial and final points and therefore does not depend on the path followed by the object finally distances always positive while displacement can be positive or negative depending on direction finally distance may be 0 even if displacement is zero distance may not be 0 like we saw displacement from A to A was 0 but in that case distance turned out to be 500 meters displacement it has to be 0 if the distance is 0 so we saw what distance and what is a displacement and now we also know what is the difference between the two.
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ICSE Grade IX English Demo Videos
Hello students this is Monica your teacher and today we are going to do very adventures and an exciting chapter from the collection of short stories and poems chapter number 9 tiger in the tunnel by Ruskin bondnow let us first know author the Ruskin bond is one of the most popular Anglo-Indian novelist and short story writer he was born in nineteen thirty-four at Kasoli in Himachal Pradesh he has received several awards for this beautiful writings he has written more than a hundred short stories novels essays and more than 30 books forchildren exclusively his writings usually revolve around the theme of nature animals life travel love and fun he presently lives at land or in mussoorie now let us know a little more by understanding the summary of this chapter it is a simple and touching story or tribal village family the sense of the story is captured in its simplicity and innocence it unwinds the story of Baldev. Who is a watch man and carry his night duty religiously it was a usual night when he was suddenly jolted by some strange sound which he later recognizes his worst fate is knocking at the door the story leaves us gaping in suspense but in the end gives a sense of content it gives us a very valuable and beautiful message life has to go on and the living have to remain now moving ahead let us have alook at the character sketch of the two main characters of the storythe first one baldev he is the central character who is a simple poor man andis living hand to mouth he’s a proud tribal man door and is an absent minded person he’s also brave encourages and sentimental and above all he is a loving Father now let us know about the second character which is tembu his son, the doting son, having profound sense of responsibility extremely brave encourages a loving son – and a truetribal boy now let us move on ahead to reading and comprehending this wonderful chapter tembu the boy opened his eyes in the dark and wondered if the father was ready to leave the hut on his nightly errands. Errands night duty so tembu will walkup wondering whether his father had left for his night duty and there was no moon that night and the Deathly stillness of the surrounding jungle was broken only occasionally by the shrill cry or for Sagada. Now deathly stillness frightening silence and Sagada is a big insect that makes a humming sound so itwas a no moon night and the absolute scary silence of the jungle was only occasionally broken by the sound of Sagada further sometimes from far off came the holo hammering off of woodpecker carried along on the faint breeze ,faint gentleso along with the gentle breeze one could hear the hammering sound of a woodpecker all the grant of a wild boar could be heard as he dug up a favorite truth but these sounds were rare and the silence of the forest always returned to swallow them up grant sound made by a pig and wild boar is a while pig so the noise made by pigs could also be heard however all sounds were not really often heard to break the silence of the jungle Baldev the watch man was awake so Baldev whose tembus’s father was now a wake he stretched himself slowly unwinding the heavy shawl that covered him like shroud so he stretched and remove the shawl which was on him a shroud is acloth covering our dead body so you’re it was close on midnight and the chilly air made him shiver so the cold midnight air made Baldev shiver.
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ICSE Grade IX Physics Demo Videos
Hello students we have already studied the Pascal’s principle and we move on to the third application of Pascal’s principle that is the hydraulic break we’re all aware that hydraulic brakes are used in cars and they use nothing else but Pascal’s principle the construction and working of hydraulic brakes is the most interesting application of the Pascal’s principle let’s take a look at the construction of the hydraulic brake now if you take a look at the diagram we know that the first thing we do in hydraulic brake is that we place a foot on the pedal now the foot placed on the pedal and the pedal is the first component of a hydraulic break so foot pedal is the first thing we need to know the second thing we need to know is that the foot pedal is connected to the master cylinder P and if you take a look at this black piston it’s the piston a so we say that the foot pedal is connected through the piston a to a master cylinder p so every card for every vehicle has a master cylinder P now to this master cylinder p is connected a pipeline R if you take a look at the pipeline it contains a liquid and in case of a hydraulic brake it is obvious that this liquid will be oil which is commonly referred to as break oil this masters Cylinder connected to a wheel cylinder and for each wheel there is a wheel cylinder which we will call this Q now this real still in the Q is connected to two pistons b1 and b2 as you can see these two pistons and then pressed against the two brake shoes which we will see other next components what is important to note is the cross sectional area of q is greater than the cross-sectional area of P so you can see that q is a bigger cylinder then P that is the wheel cylinder is greater than the master cylinder next we move on to the next component that is the brake shoes which are touching the piston the brake shoes pressed against the rim of the wheel and finally we have a spring and a spring restores the original position of the brake shoes once you release the brakes so these are the different components and this is the construction of the hydraulic brakes but let’s move on to see what is the working and how these hydraulic brakes use the principle of Pascal’s law so let’s understand Pascal’s principle in terms of the hydraulic brakes now to apply the brakes we know that the first thing we do is apply pressure on the foot pedal so once the foot body is pressed what happens is the piston moves into the master cylinder which means the piston is exerting pressure on the liquid inside the master cylinder now once the liquid is exerted with pressure we know that the liquid inside the master cylinder p will run out from the master cylinder to the wheel cylinder because of the increased pressure now there is excess pressure in the wheel cylinder but we know pressure gets transmitted equally why because of Pascal’s principle so this increased pressure in the wheel cylinder is going to get transmitted equally to both the Pistons which are b1 and b2 and this is going to make the Pistons that is b1 and b2 push outwards so you can see the increase pressure causes the Pistons to move outwards now if the Pistons move outwards who are they going to press against it is obvious that these pistons will press against the brake shoes which will then press against the rim of the wheel and the motion of the vehicle retards so this is how you apply brakes in hydraulic brakes so this is the first part of the working that is application of the brakes let’s try and understand where this Pascal’s principle fitting inside this Working so to understand that remember that the area of cross section of piston A that is the master cylinder p is less than that of the wheel cylinder q and according to Pascal’s law we know that pressure is transmitted equally so the pressure in the master cylinder is equal to the pressure than the wheel cylinder so we can write P1 equal P2 too but pressure we know its force upon area so we say F1 upon A1 equals F2 upon A2 but we know cross-sectional area of the master cylinder is less than the cross section area of the wheel cylinder and so we write that since a1 is less than a2 it is obvious that f1 must be less than F 2 and therefore F1 upon A1 can be equal to f2 upon a2 only if f 1 less than F to and from this we can see that a small force applied at the foot pedal produces a large force on the piston b1 and b2 off the wheel cylinder Q that is f1 is much less than F2 a small force f1 give you a large force f2 so we have seen how Pascal’s principle is used to apply breaks now let’s see what happens if i want to release the brakes so let’s take a look at the diagram again now in the working of releasing the brakes the first thing of course we do is release the pressure from the foot pedal so you take off your feet from the pedal and the piston is going to come back to its original position now if the piston comes back to its original position it’s obvious that the liquid will run back from the wheel cylinder to the master cylinder the Pistons will come back to the original position and the spring is going to help the brake shoes come back to the original position so the rim of the wheel is now free to move and then we can say that the brakes have been released so we have seen how to release brakes simply by removing your feet from the foot pedal and the pressure causes the liquid to run back in the master cylinder and you can start your car again so this was the working of the hydraulic brake before we conclude our conversation on Pascal’s law that is note the following things in all the three applications we learned we have to be careful that effort is less than load every time the force we applied was much less than the force we obtained that is a small force give us a large force so force applied is less than force obtained which we can say that is effort is less than load also we know that the displacement or we can say the distance moved by effort was greater than the distance moved by load whether it’s the hydraulic press where the bale of cotton moves and larger distance all the hydraulic jack but the car can be moved to a higher height or in this case the hydraulic brake where the Pistons move outwards the displacement or the distance moved by effort was greater than the distance moved by load and therefore we say that the large displacement of the piston causes a small displacement of the load and therefore productive effort and distance moved by effort becomes equal to the product of load and the distance moved by load and the product of any force and the distance is nothing but the work done so from this we can say that the work done by effort becomes equal to the work done by load and so it’s important to remember that in all these applications the work done by effort equal to work done by load also we can say that since effort is less than load we can see that load upon effort is greater than one and therefore mechanical advantage is greater than one also the velocity ratio which is distance moved by effort upon distance move by load will also be greater than 1 and therefore all these machines act like force multipliers so in any case where you require a larger force a force multiplier that is any of these machines are used thank you.
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ICSE Grade IX Maths Demo Videos
The next sum on histogram we will see is this one draw the histogram to represent the following data and the data is given like this two rows are There the first row daily sales of a store in rupees 0 to 1000, 1000 to 2000, 2000 to 3000 and so on in the second row number of days in a month 2,10,12 and so on right now the question is where to draw a histogram for this data right if you see the classes the classes are continuous so our first step the classes should be continues that is done for us right so the first column daily sales of a store in rupees the second column the frequency that is number of days in a month the classes will write them one below the other ok as it is given to us in the sum and the second column frequency also will write one below the other as it is given to us in that prop write this last row total it is not required you just require the classes and you require the frequency to draw the histogram then we’ll take up the graph paper and then we’ll prepare the x-axis and y-axis and will write X dash y dash intersecting at 0 then we are going to put the class limits on the x axis right class limits what are the classes in the sum daily sales of a store in rupees will like That ok and on the y-axis we are going to write the frequencies right so what is the frequency in this some it is number of days in a month so that is write that On Y axis number of days in a month the x-axis and y-axis we are written let us put the class limits on the x axis right now other classes starting from zero yes they are starting from zero can you see that 0 to 1000 is the first class so 0 is there on the x axis that is at the origin can you see that 0 at the origin from that zero only start 0 to 1000 and so on correct so 0 to 1000 will be the first class than 1000 to 2000, 2000 or 3000 we are leaving a gap of 2-2 centimeters and then putting all the limits we can leave a gap of one centimeter also the choices ours but we are leaving a gap of 2-2 centimeters so 0 to 1000 1000 to 2000 and so on
2000 to 3000, 3000 to 4000 and then 4,000 to 5,000 that the last one right then X axis we have put all the numbers then check the difference between 0 and the first limit and then the difference between the first limit and the second limit let’s check the difference what’s the difference between zero and one thousand the difference between zero and one thousand is 1000 correct check the next difference what’s the difference between 1000 and 2000 the difference is 1000 is a different same or not .yes it is same the difference is that same and whenever the differences are same we don’t put anything mark right since the differences are same we will not put the krink mark when do we put krink mark when the difference are not same here they are same so no krink mark the x-axis is fully ready let’s put the numbers on the y axis or the highest frequency if you see the frequency column for the highest frequency the highest frequencies to 12 and since the highest frequencies 12 and since we have 20 centimeters with us we can go for the easiest scale easiest and simplest scale which is one centimeter is equal to 1 unit on the y-axis so if this is a scale then how is our y-axis is going to progress 1 2 3 4 5 6 7 8 9 10 11 and 12 it right so we have put the numbers on the x-axis y-axis everything so graph paper is ready no one more thing is there which is that scale so let’s write the scale on the top right hand side corner we write the scale on the x-axis and scale on the y-axis on x axis what the scale, scale on any axis is nothing but gap is equal to the difference now gap take any two numbers on the x-axis 1000-2000 what are the gap we left within the two the gap we left these two centimeters and what’s the difference the difference is 1000 so two centimeters is equal to rupees 1000 is a scale the x-axis and the y-axis what is the scale any two numbers you take gap is equal to the difference gap we left is one centimeter difference is also one units or scale on the y-axis is one centimeter is going to one unit but what is the unit on the y-axis is number of days so it’s 1 centimeter is equal to one day right so graph paper is fully ready to draw the histogram how do we draw for each class you have to draw a rectangle up to the frequency the first class the frequency is 2 so you have to draw a rectangle up two what is the first class 0 to 1000 so 0 to 1000 the frequency is too many office Leave a 1 . some of us start with 1000 know what are the lower limit of the first class 0 so start from zero here start from zero. zero to 1,000 right so that will be a rectangle the first rectangle to second rectangle the frequencies up to 12 so we have to draw a rectangle up to 12 third class of frequencies 10 so draw a rectangle upto 10 forth class the frequency is 4 you how to draw a rectangle up to fourth the fifth class of frequencies 2 so we have to draw a rectangle up 2 this way we are completed the histogram thank you.
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ICSE Grade IX History Demo Videos
Hello students to read the chapter which we are going to start will teach us about the aesthetics of European society we are leaving the Middle Ages behind and we are heading too words a modern age the beginning of the modern age was marked by a phenomenal historical event called as Renaissance so let’s begin with this chapter renaissance before we learn what is Renaissance will first understand the European society of the Middle Ages dear children medieval Europe between eight to13th century has been regarded to ask the dark ages this is because Europe was politically fragmented amongst the feudal lords. This feudal fragmentation halted the social and cultural progress in all the areas of life. the Catholic Church had resumed a great Authority and power ignorance blind faith and superstition was prevalent as learning and education became limited to the church dear children but very soon Europe will witness Renaissance by the end of 13th century let us understand what is meant by Renaissance. dear children renaissance is basically a French would it means revival or rebirth this period of Renaissance was marked with revival of learning of the ancient Greek and Roman classics Renaissance resembles the freedom to think and act without being controlled by any external agency. dear children by the word external Agency I mean the church the nobility or the Kings this transitional movement from the medieval ages to the modern times took place in between 14th century to 17th century in this period there was a great trust to art literature religion politics and science so dear children renaissance is a transition from darkness of Middle Ages to enlightenment of the modern era it was characterized by the spirit of inquiry scientific temper and the spirit of humanism it is believed that Renaissance began in Florence in Italy in 14th century and it lasted up to 17th century there are various causes of Renaissance these various causes could be understood under various headings let us find out which are those reasons which led to this historical phenomenon in Europe we will learn about the causes of Renaissance under various headings these are the fall of Constantinople discovery of new trade routes decline of feudalism spread of Education Crusades or religious wars role of original thinkers invention of printing press and development of science. So children these are the most important reasons of Renaissance we will take up these reasons one by one. Let’s first understand the cause of Renaissance which is called as the decline or the fall of Constantinople. Dear children Constantinople was the capital of Eastern Roman Empire we know the city today as Istanbul. Constantinople was the center of Greek and Roman cultures but this city was captured by the Turks in 1453 A.D. Greeks and Romans scholars who stayed in Constantinople were forced to shift to Rome and other parts of Europe while these Christian scholars fled they took away their manuscripts along with them. these genius men of liberal outlook spread their new ideas and spirits they revived the interest of Greek philosophy science art and literature this revival of learning paved the way to renaissance so dear children we can conclude that attack on Constantinople was a blessing in disguise dear children we must understand why did these Christian scholars flee to Italy and why not to any other place in Europe the reasons are very clear first of all Italy stood half way between Europe and the Middle East secondly Italy was surrounded by sea it had a natural advantage with the trade was concerned Italian cities not only became the Centers of trade but also the centers of culture and learning these Italian cities were Florence Venice Genoa Milan Rome and papal States and the most important reason for these Christian scholars to come to Italy was that pope resided in Italy those days.
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ICSE Grade IX Geography Demo Videos
Hello everyone let’s start with chapter number one of geography the earth as a planet. students in the earlier days it was believed that the earth was the center of the universe. do you believe it and all the heavenly bodies of the universe we’re moving around it however today it is an accepted fact that Earth is one of the eight planets that moves around the Sun. the Sun is one of the many stars in the universe clusters and start forming a narrow band in the sky are called as galaxies. The word cluster means a group of similar things all occurring closely together and galaxies is formed by clusters of billions of stars the Sun and it’s planets together from the solar system in the solar system is the part of the Milky Way galaxy now let’s gather information about the Sun as a star. The sun like all the stars is a hot ball of gas. the diameter of the sun measures 13 lakh ninety two thousand kilometers and students believe me the diameter of the sun is hundred and ten times larger than that of the earth even the volume of the Sun is 1.3 million times larger than that of our planet earth. the outer layers exert great pressure towards it core or the innermost layer this is because of the huge size of the Sun. Nuclear fusion takes place here due to the great heat nuclear fusion is nothing but a nuclear reaction in which two or more atomic nuclear collided at a very great speed and they join to form a new type of atomic nucleus in the case of Sun the nuclear fusion process turns the hydrogen gas into helium gas and therefore releasing large amount of energy this process occurs in the innermost part of the Sun that is the core of the Sun. the energy which is really is in all direction is in the form of electromagnetic waves these include infrared rays ultraviolet rays as well as radio waves there are larger dark spots on the surface of the sun for example the one which you see highlighted on the screen they appear dark because they are cooler and they have lower temperature than the surface of the sun these dark spots are called as the sun spots. a typical galaxy may contain one lakh million stars the Milky Way galaxy the galaxy to which our sun our solar system belongs to is called as our galaxy or we also call it as the home galaxy now let’s get that information about difference between the planet and star. the stars like the Sun radiates heat as well as light planets have no light of their own this stars are large burning masses which are located very far away from us the planets are solid bodies nearer to us. The star moment is very slow in comparison to the planets all the planets revolve around their stars in a fixed path and this path we normally call it as orbit. The stars make large clusters which we call s galaxies a typical galaxy we already know contains more than one lakh million starts the Milky Way to which our son belongs to is called as our galaxy or the home galaxy. Planets do not make any such clusters.
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