State Board Commerce (XI-XII) - Test Papers
KARNATAKA STATE BOARD XI PCMB Chemistry Demo Videos
Hello students welcome to the new chapter called state of matter in this chapter we are going to learn some interesting facts about the word matter so in this module will learn introduction to state of matter. let me start with the word matter as we all know matter is anything that occupies the space possesses mass for example this chair and table or a glass of water or some balloon containing air so if I concentrate on this I come across with the new classification that matter is going to get classified into three different types that is called solid other one liquid and one more is called gases so along with these three we having some more state of matter like plasma boseeinstein condensate, fermionic condensate, quark condensate thought wave along with these three so let me concentrate on these three types called solid liquid and gases . if u look at these pictures you can come across with the some interesting facts that the faster picture is tightly bond nothing but solid second one is slightly distributed nothing but liquid last one is completely dispersed nothing but gases so by looking at this picture I think I can make out some interesting points with respect to this point number 1 if I concentrate on shape for solid this is perfect If I concentrate on liquid there is no perfect shape if I concentrate on gas and similar to the liquid there is no shape for gas also. If I concentrate on volume solid has got volume liquid has got volume but there is no volume for gases. I got there intermolecular force of attraction and on the word about that nothing but this particular word is very much essential for these two particular parameter for shape and volume so what is intermolecular force of attraction it is the attraction between two atoms if it is very much strong I will be having a solid shape but it is very ,very less then there is no shape and there is no volume so if I concentrate on intermolecular force of attraction it is very much strong in case of solids it is very weak in case of liquids and very week in case of gases so If I want a next point nothing but packing efficiency if I concentrate on packing solid are having closely packed structure if I concentrate on liquid is loosely packed if I concentrate on gases it is very loosely packed if I concentrate on next word called density we know the word density what is density it is nothing but mass by volume . if I concentrate on packing of this particular thing it is closely packed nothing but mass by volume is more in case of solids . so in case of liquid it is slightly less in case of gases it is very very less there for density is very high in case of for solids and it is very least in case of gases and is intermediate to solids and gases in case of liquids. So in the next point we are going to learn about the word called flow ability so the word of flow ability means that is the ability to flow which is maximum in case of gases and less in case of liquids least in case of solids. if I concentrate on compressibility it is nothing but ability to get compressed it is very high in case of gases and less in case of liquids which is very least in case of solids . so there are main two parameters or condition by which I think these particular matters or wearing those two are temperature and pressure . if you concentrate on solid I can interconvert this solid into liquid just by heating and I can interconvert this liquid into gas just by heating so there is interesting phenomena that I can convert ice into water this water into steam just by heating so temperature, so the temperature is the main criteria to convert solid into liquid, liquid into gas similarly I can convert gas into liquid, liquid into solid by applying pressure . so these two are very interesting condition by which I can convert a solid into liquid , liquid into gas now will concentrate on a new concept where and temperature will play a waiter roll to convert gas into liquid that means at the high temperature and low pressure gases will exist at the low temperature and high pressure liquid will exist there for transformation of liquid to gases can be done by wearing this two condition so we have to concentrate on high temperature low pressure of gases low temperature and high pressure for liquids .
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KARNATAKA STATE BOARD XI PCMB Maths Limits Demo Videos
Hi I’m Hari Prasad let us start the chapter limits in this chapter we are going to learn how to find out the limit of the function and what do we mean by limit of a function let us start module number one in this particular module we are going to learn what is the meaning of the word tending to let us start the chapter now meaning of X x tends a is what we have to learn first so immediately the question that comes to my mind is what is the meaning of X tending 2 or X tending to any particular number a in general so it can be particularly X tending to 2, X tending 3 something like that so what is the meaning of that does it mean x is equal 2 does it mean know that x is equal to something else so answer this particular question will consider the following example consider boy who always covers fifty percent of the total distance that means the boy covers five meter for the first time so where he will be he’ll be at five meter mark the boy will cover all fifty percent of the remaining five meter that means he will cover all 2.5 meter for the second time third time he will cover 1.25 meter and so on if this is the case when the boy will be exactly on 10 meter mark can you predict the answer is the boy will be never on 10 meter mark but he’s very close to 10 meter mark right similarly when we write X tending 2 we mean that X is very close to two but it is not equal 2 consider the number line we have minus 1 0 1 2 3 and so on when x tends 2 to it can be close to two when I say close to two it can be from the left side or it can be from the right side also write suppose if I say x tends 2 and if X’s or close to 2 from the left side then it can take the following values can you get what are the values it can take x is equal to 1 .8 is possible it can take 1.9 yes it is close to 2 ,1.99 yes it can take these values right and one point nine nine nine yeah still very close to 2 and so on there are many infinitely many values that it can take but when X tends to 2 if X is close to two on the right then it can take the following values which are the values can you guess the point 2.8 can take it can take 2.2 it can take 2.1 and 2.01 so on it can take many other values right is so now the question is clear to us let us now talk in case of general elements like X and a, let X be a variable is the meaning of variable quantity which keeps changing and a be a constant with the meaning of constant quantity which has a fixed value right if X takes the value near Nearer to a then we say that e tendens to a and we write it as X arrow mark a We write it as does x tends to a note that in this case X cannot be equal to A and we are not specifying any manner in which X should approach a that means it can approach to a from left as well as it can approach from right now when X tends to a from the left we have the following situation if X approaches a taking all values less than a but Nearer to a then we say that extends to a from the left we write this as extends to a and we put a small minus over a this minus is not to be used in any of the calculation similarly when X tends to a from the right we have the following situation if X approaches a taking all the values greater than a but nearer to you a then we say that x tends to a from the right and rewrite it as x tends to a plus we write small plus sign over a like this is the notation that you need to remember thank you.
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KARNATAKA STATE BOARD XI PCMB Physics Demo Videos
Welcome dear students welcome to the chapter thermodynamics in this chapter we start with knowing the basic terminologies in this module because understanding these basic terminologies we can understand the chapter better ok let’s see what is the basic terminologies that we are going to studied in this module very very basic terms involved in this chapter first of all what do you mean by thermodynamics , thermodynamics is a branch of physics which deals basically with the conversion of heat energy into mechanical work or mechanical work into heat energy so it is the branch of physics which deals with a transfer energy from one place to another and conversion of heat energy into mechanical work or vice versa that is thermodynamics for me. Let’s see a simple example I got a cylinder me with me which is fitted with piston you can see on the screen and which has ideal gas in it. I supply heat energy how much I supply heat energy dQ amount of heat energy has been supplied and this energy what it does please observe that then you understand the meaning of thermodynamics this dQ supplied increases the volume of gas that is implies pushing the piston upward so dW amount of work is done how much work will be done dW amount of work is done so heat energy supply is converted into work and that is what is thermodynamics all about yeah let’s try to understand different types of system . what do you mean by thermodynamic system surrounding all that thermodynamic system is the quantity of matter certain quantity of matter having fixed identity and mass let’s see what is that A certain quantity of matter part of the matter having fixed identity and mass we call it thermodynamic system example, don’t think big about thermodynamic system is little water you’re got going to boil that and then that water becomes a system for you maybe I have gas in a cylinder that is a system for me look at this example water in a beaker may be 50 cc water Is that it is a system for you , you are expecting that , yes look at that In a container I’ve got gas that is a system for me having fixed identity and mass let’s see what is surrounding you must understand that anything other than the system in this universe become surrounding matter outside the system that becomes surroundings . so you have to understand that thermodynamic system continuously interacts the matter outside the system and that matter outside the system we are calling it as surrounding look at that delicious coffee may be a tea is presented in the cup that is the system for me now this system is a tea or coffee remember it interacts something outside matter outside and that part which is outside the system we are calling it as surrounding we go into different types of system right now what do you mean by open system , open system involves exchange of heat energy and matter between system and surrounding that system I m calling it as open system if there is exchange of heat and matter takes place between system and surrounding call that system as open system look at this piston and cylinder you can see in the picture which has gas in it and you supply the heat energy when you supply heat energy you can see that the gas expands work has been done yes excess heat energy is there what happened to the excess heat energy that will got . so it has got exchange of heat energy as well as matter and that system we are calling it is the open system lets go to the closed system means what a system in which you have got only action exchange of heat but not matter that is absolutely no matter exchange yes, if the exchange is only heat energy not the matter between the system and surrounding we call it as a closed system. cylinder provide with the piston having the ideal gas you supply heat energy remember only the heat energy exchange between the system and surrounding not the matter you can seen that work has been done but there is no matter to exchange let’s see what is that work done dW amount of work done but no amount of matter exchanged between system and surrounding yes will know it isolated system no exchange of heat and matter between the system and surroundings let’s see that example no exchange of matter and heat between the system and surroundings look at this thermally isolated system nothing is going to inside neither heat not the matter the system is called as isolated system non conducting wall … thank you.
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KARNATAKA STATE BOARD XII PCMB Biology Demo Videos
Welcome students we are here with a beautiful and interesting chapter in biology i.e. health and disease. in this chapter we will talking about the basic different type of disease and then we followed by the very important system of our body i.e. the different mechanism which helps to fight those disease and finally brief talk about the different aspects of addiction. Now lets us talk about very first module in this module we will be dealing with the erraticallypart what is basically health. Let us talk basically what is health and now it is very simple question for you students and very basic question but we all need to know what is health, yes let us taking an example. In this instance if you see the person here has got some disease yes we say that normally they are not healthy. Then does no disease means a healthy state. Let us talk about that now yes basically health doesnot simply mean the absence of disease or physical fitness then what is health? Yes Health is basically defined using a 3 important dimension. Can you guess the three important dimension what it could be? Ya first one here is the physical. And second one is very important is the mental and third one is going to be a social. Yes student Let us talk about them in detail now basically health is defined as a state of complete physical well being. Yes student first of all as a state of complete health i.e physical well being. Next important thing and what is this indicate that a person is physically healthy but you know when they are bound with too much of stress or it can be any in balances in the body and it interfused called the depression. Yes student and they play very important role and here if u see the person has to be healthy then it is healthy only if they have what state yes I mean to say a complete state of what complete mental well begin and that mean the person should not have any short of depression also. Next important thing what is this? Yes I am talking about maintaining good relationship with people in society. And here that is nothing but social well being let us try to summarized them now. Basically health is defined as a state of physical than the mental and social well being and very importantly and not merely absence of disease or infirmity. What is the infirmity? Yes infirmity meaning a state of weakness or debility. Now next important thing how do we remain a healthy? a very basic answer and very important answer here giving is hygiene. What is the hygiene and write students is the science of health which actually aims at preserving then maintaining and the improving. Yes the health of the it is only individual, ya it is individual and the community as a whole that is how can maintain a hygienic condition. Next important thing here is how to remain a healthy or how to maintain a good health and then very important thing practiced by us the first one , can you guesses the first one going to be , yes very right that is balanced diet . next important thing that is regular exercise and yoga meditation etc. and next thing is maintain a personal hygiene ,next is right attitude of mind and finally a cultivating a good habits all if this maintain well help us to maintain a good health now if this all are not maintained what is going to leading do, yes it might your condition called disease what is disease let us now to defined that now disorder of structures and functions basically other abnormal condition all of them collectively is called as disease . Now in this module just we have to talk about a brief outline of that disease but later taking about some example also. Now here in this module we have discuss about the health and the basic concept of hygiene and also outline disease. Yes in the next module we will talking about type of disease. Ya student we will right back in a next module. Bye then thank you.
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KARNATAKA STATE BOARD XII PCMB Chemistry Demo Videos
Hello students welcome to module number 1 let us discuss something about solid state in this module we will discuss some introduction and classification of solids. My dear students we know that anything which occupied space and has definite mass as known as matter. A matter exist in a 3 physical state the first one is a solid second one is liquid and third one is gas and these three physical state are inter convertible by changing the condition of temperature and pressure the solid on heating it is changes to a liquid. On heating the liquid changes into the gas by cooling the gas is converting to the liquid . and again cooling the liquid changes into the solid . There for the 3 states of matter are interconvertible by change in the temperature or pressure now let us scientist has discovered the two states of matter and these are plasma and Bose–Einstein condensate. The discovery of fifth state of matter was done by a great Indian scientist sattindranath Bose and well known scientist Albert Einstein. These 3 physical state of substance are mainly depends on two factor the first one is inter particles attractive forces and second one is thermal energy. The inter particles attractive forces constant particle tends to keep closer but thermal energy tends to keep them apart. Now students what are the solids the solids are the substance which have definite shape and definite volume. For example the TV, door , laptop these have definite shape and definite volume . These are the examples of the solids. Now what are the general characteristics properties of solids are the first one the solids have fixed mass, shape, volume and density for example this box this box has definite mass definite volume definite mass definite shape also. In solids the intermolecular distance is very small take a look here the particles are closely packed there for intermolecular distance are very small. And if intermolecular distance are very small means what is the force of attraction .the force of attraction that is intermolecular force of attraction is very strong and coming to the last point the solids are hard, rigid and incompressible. These are properties of solid. Now the classification of solids based on the nature of orderly arrangement of constitute particles in 3 dimensions. The solids are classified into two types first one is crystalline solid and second one is amorphous solid now the students what are these crystalline solid and amorphous solid .their a long range orderly arrangement of constituent particles in known as crystalline solid . and there is not long range orderly arrangement of constituent particles are known as amorphous solid .for crystalline solid examples are quartz , sodium chloride etc. for amorphous solid examples are polyvinyl chloride, glass fiber etc. now the properties of crystalline solid the first property is crystalline solids have Sharp melting point and definite heat of fusion why crystalline solids have sharp melting point because the strength of all the bonds between the particles are equal there for crystalline solids have sharp melting point. Ice is an example of crystalline solid the melting point is zero degree Celsius coming to the second property of crystalline solid that is anisotropy. There is many properties which have different values in different directions for example the thermal conductivity , electrical conductivity , reflective index , mechanical strength are different along different directions in one directions the compositions of solid is green purple , green purple and other it is purple, purple, purple, purple since the composition of solid changes with direction has the values of physical properties also changes therefor it exhibit work and isotropy nature or an isotropy now for this plain solid start and is appropriate in nature now what are the differences between crystalline and amorphous solid coming to the first parameter that is arrangement there is a long range orderly arrangement of particles in crystalline solid in case amorphous solid that is short range of orderly arrangement i.e. there is no long range orderly arrangement of particles in case of amorphous solid the second property is melting point crystalline solids are have sharp melting point amorphous solid do not have sharp melting point because the strength of all the bonds between the particles are not equal there for amorphous solid don’t have Sharpe melting point and third property heat of fusion crystalline solids have definite heat of fusion and amorphous solid no definite heat of fusion. And coming to the fourth anisotropy and isotropic nature .the crystalline solids are anisotropic in nature and amorphous solids are isotropic in nature and coming to the fifth point nature. Crystalline solids are also known as true solid and amorphous solids are also known as a pseudo solid and coming to the last point shape crystalline solids have definite geometrical shape but amorphous solid has irregular shape. Thank you students.
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KARNATAKA STATE BOARD XII PCMB Maths Demo Videos
Hello students welcome to this new chapter probability. Where we are going to speak about condition of probability in this module. Now we should have strong knowledge about probability what you studied in your 11th std. You were studied about definition of probability also you have studied about addition theorem rich to tell them. We have proceed further same concept of probability which is chapter for you in the 12th. Lets consider the definition of conditional probability , if E and F are two events associated with a same sample space of a random experiment the condition of probability of the event E given that F has occurred is given by P of E given by F is equal to P of E intersection F divided by P of F where P of F is not equal to zero remember this is a formula of conditional probability now I will note taken on that E given F already seen what about P of F given E what happen what will be happen there P of F given E is equal to P of F intersection E divided by what dived by P of F making sure the denominator is not zero so that is a note you have let me proceed further there are some properties of conditional probability let see one by one and we see proof of it as well the first property says probability of S given F is equal to P of F given F is equal to one . The second one says probability A union B given F is equal to probability P of A given F + probability B given F – probability A intersection B given F And third one says probability E compliment given F is equal to 1 – probability E given F this are the three properties let see solution one by one. Let me start with the first probability S given F I understand the condition of probability e given F is equal to E intersection by F what will S given F it will be P of S intersection F divided by P of F remember this what is after that should be in denominator S given F what is second should be in denominator. now what about the proceeding part of this S intersection F what you understand for this S stands for sample space and I know that F is a subset of sample space F is an event is a subset of sample space and what about the intersection obviously it is F P of S intersection F, P of F divided by P of F it is 1 so I have got first part of first property , what about second part of first property P of F given F it is according the formula of condition probability I can write it as P of F Intersection F divided by P of F and F intersection F because F is Same as F it is contained so I can write F itself P of F divided by P of F is equal to 1 so we have got proof of 1st property . let me go with the proof of second property . let me start P of A union B given F according to condition probability formula we can write it as P of A union B intersection F divided by P of F now what about the numerator so I can use distributive law A union B intersection C is equal to A union C intersection B union C, same thing I will write here P of A union F intersection B union c divided by as it is P of A . now what about numerator use the addition theorem of probability and split the numerator as it is what I get that I will get it as P of A intersection F + P of B intersection F – P of A intersection B intersection F divided by P of F . now I will split it into three parts I will get it as P of A intersection F divide by P of A + P of B intersection F divided by P of A – P of A intersection B intersection F divided by P of F now I can recall the condition of probability . earlier we have seen left hand side right in the right hand side now see the right hand side right the left hand side according to that the first term P of A given F what is the second term P of B given F third term will be p of A intersection B giving F and this is the proof of second property I can take a note regarding the particular property when A and B are mutually exclusive intersection is zero their for I can get P of A union B giving P of A giving F + P of B giving F only A and B are mutually exclusive events . let me go the property no. 3 proof , we know that the first property P of S given F is equal to 1 also I know E union E compliment any event union is compliment same as the sample space let me replace s by E union E’ do you think E union E’ are mutually exclusive yes they are mutually exclusive according to note mentioned earlier A union B giving F is equal to P of A giving F + P of B giving F , and I use that particular note P of E Giving F + P of E’ giving F is equal to 1 there for the taking 1st term to right hand side I get P of E’ giving F is equal to 1- P of E giving F that’s a required proof of the property so these are the 3 properties what we have conditional probability , Thank you .
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