Khan Academy — transcripts.

1Periodic trends and Coulomb's law | Atomic structure and properties | AP Chemistry | Khan Academy- [Instructor] In this video we're going to look at trends for the periodic table of elements for dimensions like ionization energy, atomic and ionic radii, electron affinity, and… 2Applying signed number addition to elevation situations: writing equations- [Instructor] We're told that Fiona starts at an elevation of negative six meters in an underground subway station. After rising M meters on an escalator, Fiona reaches an… 3Applying percent error with an underestimateRocío Elena estimated 132 people would attend the wheelchair basketball championship. This was an underestimate by 25%. How many people actually attended the wheelchair basketball… 4Finding the volume of a prism with a polygon base on a gridThe base of a hexagonal prism is shown on the grid. Each square on the grid represents one square unit. The height of the prism is five units. What is the volume of the hexagonal… 5Distances in the coordinate plane (between reflected points) | Khan Academy- [Tutor] We're told point R has the same coordinates as point P, except it's Y coordinate has the opposite sign. Point R is at two, common negative six. What is the different… 6Interpreting mean | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] We're told that two basketball teams recorded the number of points they scored in each game during a season. The results are shown in the dot plots and they say… 7Modeling distance over timeAt its current constant speed, a train travels 50 km in 10 minutes. And they're let T equal time in minutes and D equal distance in kilometers. Part one, well, actually, I… 8Categorical data sets | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] A music teacher asks, "Which instrument does each student play?" What type of data set does this question produce? Pause this video, have a go at that. Okay, so it… 9Interpreting variability | 6th grade math (Illustrative Math-aligned) | Khan AcademyTwo dart throwing robots are being tested for how consistently they hit a target. The results are shown in the dot plots and each dot represents the distance in centimeters from… 10Identifying identical triangle copiestold that Diego drew We're told that Diego drew this triangle and then we're asked which triangles are identical copies of Diego's triangle. Pause this video, have a go at that.… 11Determining whether a sample is representative using centerA pet shelter recorded how many animals were adopted each month for the past 10 years. This includes 120 months of data. Yeah, that makes sense. 10 years times 12 months per year.… 12Classifying outcomes using likelihood termsWe're told that Mr. Sanchez is handing out notebooks to students. He has 40 notebooks on a shelf, four green and 36 blue. Mr. Sanchez randomly selects one notebook from the shelf.… 13Identifying valid simulationsWe're told that at a movie theater, about 40% of the visitors buy popcorn. The manager wants to simulate whether each of the next 50 visitors will buy popcorn. He places five… 14Comparing populations using IQRThe blocks the box plots show the number of minutes spent waiting in line by a random sample of visitors at two amusement park rides. What we see here, the box plots in each case… 15Comparing two experiments to predict the better chanceWe're told Nina is at an arcade and wants to win a stuffed animal from a claw machine. She records the results of people playing two different claw machines. So, on the Lucky… 16Selecting a valid simulation for a multi-step eventA package delivery service successfully delivers a package on time 70% of the time. Which simulation could we use to model whether at least three out of the next four packages are… 17Matching a probability value to a likelihood termWe're told that Kiara's phone is set to randomly choose a notification sound whenever she gets a message. The chance that the chime sound plays is 0.5. Which term best describes… 18Finding the volume of a prism with a polygon baseThe image shows the trapezoidal base of a prism. The prism has a height of eight units. What is the volume of the prism? So, pause the video and try that on your own. Okay, so… 19Equal and equivalent expressionsAll right. What we need to do for each of these statements, we need to compare these expressions. And in this blank, we either need to put a an always, a sometimes, or a never.… 20Labeling axes to fit data sets | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Narrator] So we have some data here. It says weekly average high temperature in Philadelphia. And what we wanna do is plot this on a coordinate grid. Now, to do that, let's get… 21Making a prediction based on results from a single experimentWe're told that Renato is practicing his tennis serve. He serves the ball 12 times and records whether each serve lands in the service box or outside the service box. So, he got… 22Numerical data sets | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] In this video, we're gonna think about types of datasets. And when we think about datasets, broadly speaking, we can divide them into categorical, categorical and… 23Special polyhedra: cube | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] What we're gonna do in this video is think about how to find the volume of a cube. But before we do that, I wanna think about or maybe review how we find the area… 24Median | Data sets and distribution | 6th grade math (Illustrative Math-aligned) | Khan AcademyIn this video, we're going to talk more about what it means to have a typical value for a set of data points. Now, when we say typical, we typically we typically I'm not overusing… 25Using volume for missing side length (mixed numbers) | Khan Academy- [Instructor] We're told a rectangular storage box has a volume of 7 1/2 cubic inches. The box is three inches wide and two inches tall. What is the length of the storage box? So… 26Interpreting constant of proportionality in graphsWe're told the graph shows the relationship between the length of time Aiko spends folding origami. So this right over here, okay, this is the length of time in the vertical axis… 27Modeling fraction equations with tape diagrams: bike route | Khan Academy- [Instructor] Marcus is planning an 18-mile bike ride. He rides 12 miles and takes a break at a park. He uses the model shown to represent how much of the route he has completed.… 28Modeling fraction expressions with tape diagrams: pasta salad | Khan Academy- [Instructor] We're told a pasta salad recipe calls for three cups of chopped vegetables. Asha chopped eight cups of vegetables to make batches for an event. Use a tape diagram… 29Introduction to AP Physics C: Mechanics | Khan Academy(equipment rattling) - [Instructor] How does NASA train astronauts for a weightless environment here on Earth? How do we figure out the minimum speed needed to escape Earth's… 30Mean | Data sets and distribution | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Presenter] We're told the following table shows the number of books read by each student during a reading challenge, all right? And then it says, find the mean number of books… 31Comparing triangles by analyzing angle and side arrangementsConsider the following triangles. Which statements about the triangles are true? And they want us to pick two answers. So, pause the video and try this on your own. Okay. So, the… 32Estimating a population count from a random sampleA school cafeteria wants to estimate how many students will choose each lunch option next week. A group of randomly selected students were asked which lunch option they would… 33Finding a missing dimension of a prism using the volume formulaThe base of a prism is shown on the grid. That's this right over here. Each square on the grid represents one square unit. The volume of the prism is 56 cubic units. What is the… 34Comparing populations using MADTwo food trucks recorded the number of customers served per hour in a random sample of hours. The dot plots show the results and the mean and mean absolute deviations, MADs, for… 35Identifying the most representative sample using shape, center, and spreadThe dot plot shows the number of minutes 30 students spent practicing a musical instrument after school on Tuesday. So we're su assuming that this is the population. They're… 36Determining if a triangle is possible given two angle measuresHow many unique triangles can be drawn with 110° angle, I'm assuming, and a 75° angle? I just forgot to write angles here, but how many unique triangles can be drawn with a 110°… 37Missing information: rate problems | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] We're told that Amaru bought five kilograms of apples and two kilograms of strawberries to make treats for a bake sale. What additional information is needed to… 38Reasoning with tape diagrams to solve equationsSo, we're told the tape diagram represents the equation 7 * (x + 2) = 77. And what they want us to do is figure out the value of x. So, pause this video and have a go at that… 39Modeling expressions with mixed numbers: bracelets | Khan Academy- [Instructor] "Josiah is making identical beaded bracelets for each of his friends. So far he has used 22 beads to complete 2 3/4 bracelets. How many beads are there on one… 40Relating decimal multiplication to fractions and place value | Khan Academy- [Lecturer] What we're gonna do in this video is review what we know already about how we can go between fractions and decimals, and then we'll think about all the different ways… 41Solving money problems with decimals | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] We're told Yonna bakes three batches of cookies. Each batch costs $4.75 to make. She sells 28 of the cookies at a farmer's market for $1.25 each. What is Yonna's?… 42Drawing conclusions from sample dataAt two farmers markets, vendors recorded the amount of money spent by customers during a visit. The median amount spent for a sample of customers at Maple Grove Farmers Market is… 43Determining triangle uniquenessA triangle has an angle measuring 40° a 6 cm side opposite the 40° angle and another side that is 8 cm long. How many unique triangles can be drawn to fit this description? It's… 44Kinematic quantities: Accumulations of change | AP Physics | Khan Academy- [Instructor] If we are given an acceleration time graph, how can we use that to plot the velocity time and the position time graph? That's what we want to explore in this video.… 45Identifying bases and heights of parallelograms | Khan Academy- [Narrator] So I have two parallelograms here and we've labeled the base of each of these parallelograms. The base they're saying is the side that I am recoloring in as red. And… 46Identifying equations from visual models tape diagramsThe tape diagram represents an equation. Write an equation to represent the tape diagram. So, pause the video, have a go at that. And then you can actually try to find the value… 47Kinematic quantities: Rates of change | AP Physics | Khan Academy- [Lecturer] Humanity is incredible at prediction, we can figure out the exact velocity an airplane needs to take off, we can even precisely time solar eclipses years in advance.… 48Volume of a cube | Area and surface area | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] So we have two different cubes here, and I wanna figure out their volumes. For each of them, we know one of the side lengths. So why don't you pause this video and… 49Reasoning with tape diagrams to connect situations and equationsWhereas, which situation could the tape diagram represent? So, pause the video, have a go at this before we do this together. All right, now let's do this together and let's see.… 50Estimating probability from a simulationA library's returned, a library book is returned late 20% of the time. A librarian wants to predict how often at least one of the next four books checked out will be returned… 51Comparing two probability values expressed in different formsA music app recommends songs from different genres. The app shows these chances for the next song. So, there is a 40% chance that the next song is pop. There is a 0.45 chance that… 52Part-to-part ratio models | 6th grade math (Illustrative Math-aligned) | Khan Academy- [Instructor] We're told to select all statements that correctly describe this ratio relationship between the circles here and the squares here. So pause this video, have a go at…