in this video i'll talk about how to measure the overflow of water from a completely filled glass and the overflow happens due to the thermal expansion so we have a pydex glass this part is glass and the volume of this pyrex glass is 500 cubic centimeter and it is completely filled with water at a certain temperature in this case it is room temperature 20 degrees celsius and when you heat it the 250 degree celsius some of the water overflows you see this is the overflow water that's the over flow water and now you need to find out what's the volume of this overflow water the given the quantities are the coefficient of expansion of this pyrex class and the coefficient of expansion of water so what happens let me talk a little bit about this one when you heat it both the pyrex glass and the water both expands together and in this case you have noticed the expansion of volume expansion coefficient of water and the paris class are different what does that mean this means the both the pyrex class and the water will have a different change in the volume after hitting it and as the volume expansion of water is significantly greater than the volume expansion of pyrex class there will be more change in the volume of the water than the pyrex class so the pyrex class will expand less and the water will expand more because of the higher coefficient of volume expansion of water and as a result the water will overflow but still the question is by how much and we're going to calculate here first the way we do this problem is first we're going to calculate the change in the volume or increase in the volume of the vertex class so how do we measure it we measure it by using this equation that's the very standard equation for calculating the change in the volume due to the thermal expansion and the p here stands just for the pi x and beta beta is the coefficient of volume expansion of volume expansion and and this quantity is given and v o p the v is the v o s stands for the initial volume of the pyrex class and the p stands for the pyrex class and delta t is the change in temperature all the quantities are given so the beta for the parallax class is 0.1 times 10 to the negative 4 is given here and the volume the initial volume of the pyrex class is given here it is 500 cubic centimeter which is cubic centimeter and the change in temperature is because this one was filled at the room temperature and after heating we go to the temperature of 50 degree celsius so the change will be 50 minus 20 that is 30 degree and all we need to do is a simple map plug in in your calculator and you'll get this value 0.15 cubic centimeter so that's the change in the volume of the the particles class so do not go by this figure this is has been exaggerated so that if the change in the volume of the pyrex class is 0.15 now let's do exactly the same calculation but now for the water for the water again we'll use the same formula here and this time we're going to use the beta which is the volume coefficient of volume expansion for water and for water this value is 2.2 times 10 to the negative 4. so we have 2.2 times negative 4 and the volume initial volume of water and this pyrex glass was entirely filled with the water so the volume of water was also 500 cubic centimeter and again the change in temperature is exactly the same for both which is 30. then what you get the value is 3.3 cubic centimeter so this one expands 3.3 cubic centimeter and this one expands 0.15 cubic centimeter so the overflow of the water will be 3.3 minus 0.15 which is 3.15 cubic centimeter water so that means the water that has overflown to the ground is 3.15 cubic centimeter okay so this is a very simple steps to calculate the amount of water overflow so all the things you need to remember is the coffee center volume expansion if if let's say you have chosen the your beaker or something which has higher coefficient of volume expansion then that means the water if the pyrex glass let's say for example if the pyrex glass and the water had exactly the same coefficient of volume expansion then the water would not have overflown because both x both would have expanded equally so this differences in the coefficient of volume expansion will result in overflow so this is it from this lecture if you have any questions any comments please write down in the comment section below and do not forget to like share and subscribe the channel thank you very much