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An experiment in losing your marbles.....

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talking about speed and velocity is great and drawing graphs and motion maps [Car travelling fast and graph appears]

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super helpful but it's kind of weird to think about motion without seeing

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anything you know actually move so we're going to take care of that right now

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yep it's time for an experiment okay first off we need our lab equipment [Lab equipment appears]

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don't worry no Bunsen burners for this one for now we need the following a

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meter stick tape masking tape or scotch tape would be ideal because we're going

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to be writing on it meaning we'll need a marker a plain old piece of paper which

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is going to be origami'd into a launch shoot a hole punch a pencil or pen or

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even a twig from the backyard if it's as wide as a pen or a pencil something

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fairly long and skinny basically a book not a comic book either something with

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an inch or two thick a marble or a ball bearing nothing too wide here something [Assortment of stationary equipment appears on desk]

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to keep time with a stopwatch if you're a track coach the rest of us might just

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use a stopwatch on our phones clock and we'll also need a long spot of clean

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floor here's the whole list hit pause and go start hunting and gathering got

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everything or figured out substitutions for everything you're missing good so

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what are we going to do with all this stuff we're gonna find out how long it

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takes our marble to go different distances which means we'll be dealing

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with displacement and velocity all that jazz and we're going to track our data

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because we're good scientists like that and then then we'll calculate the

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velocities for our measurements but let's not get too far ahead of ourselves [velocity calculation appears]

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as we can see this experiment has some assembly required so let's hop to it

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first of all fold the paper in half lengthwise then fold that in half again [Piece of paper folded twice]

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the other way we're just making it a little stronger so go ahead and tape the

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side so it doesn't open at the folds now we're going to make a track for our

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marble so fold it into thirds and make sure the track is wide enough for our

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marble to roll freely not too wide we don't want it bouncing from side to side [Marble rolls across folded piece of paper]

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this is going to be our launch chute eventually we're going to be making a

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ramp with this shoot so pick which end is

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going to be the bottom where the marble will come rolling out then with our

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marker make marks on the sides at 4 centimeters and 8 centimeters up from [Person marks at 4cm and 8cm on piece of paper]

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the bottom you'll make these too high up the sides we don't want them higher than

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the top of the marble now go ahead and punch holes at those marks save the

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scraps for the next time you need confetti and slide your pencil pen

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Tinkertoy stick whatever through the holes like this this is going to serve [Pencil through holes in piece of paper]

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as our starting gate for the marble so we want to be sure we don't have a

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struggle getting the pen free if it's a tight fit just make the punched hole

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a little wider and put a couple of pieces of the tape over the top to hold

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the walls in place, chute assembly complete time for a little housecleaning

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no really we need to clean the floor get a wet towel or a mop and wipe down a [Man fetches a mop]

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good long spot for our marble to roll on we don't want our experiment to fail

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because we run into a glob of yesterday's oatmeal Plus mom will be

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super happy doing science and cleaning the floor major brownie points! [Mum holding brownies and slips on the floor]

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Once that's done go ahead and set up the chute tape the bottom to the floor then

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rest the top on the book so we have a ramp time for some testing..send your

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marble down the chute and see where it goes

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is it going straight running into any bumpy patches if the marble is going all [Marble rolling on the floor]

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wonky you might need a different patch of floor to work with but if it's all

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good time to mark our track use the meter stick to measure a meter from the

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end of the chute mark that spot with a piece of tape and write the distance on

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the tape go ahead and do that for meters 2 through 5 also you're probably itching

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to get started by now but before we can get that marble moving we need to be

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ready to collect the data we'll need to have two separate grids one for fast and [Fast and slow grids appear]

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one for slow and each grid needs to have 5 spots for distance 5 spots for time

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and 5 spots for velocity got that done then let's get rolling go ahead and set

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up your starting gate slide the pen or whatever through the set of the holes

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closest to the floor then load up the marble into the chute so it's resting [Person places marble into chute]

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against the pen get your stopwatch ready pull out the pen and start the stopwatch

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when the marble hits the end of the chute stop the clock when the marble

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hits the 1 meter mark yay we officially have data since we're using the starting

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position close to the ground we'll mark down our measurement

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in the slow grid put the distance in the distance column and the time in the

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time column we probably didn't need to tell you all that did we will do the

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velocity when we're done running all the distances so pause this and find your

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marble hopefully didn't end up under the fridge

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got it excellent get your starting gate ready load up the marble and time how [Marble released from starting gate]

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long it takes to hit the 2 meter mark write your data down and repeat for meters

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3 4 & 5 then do it all again for the fast starting position and consider all

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this marble chasing your cardio work for the day all right got all your times for

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each distance this is a time when distance and displacement have the same

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value by the way we should all have 10 measurements let's go ahead and find the

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velocities the equation for velocity is the change of displacement divided by [Equation for velocity appears]

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change in time for this experiment the starting time and displacement will both

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be 0 so we have to divide each distance by the time it took the marble to reach

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it so go ahead and record the 10 velocities and now it's time to get [Velocities appear in fast and slow grid columns]

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graphic don't worry...just mean we're going

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to be drawing take a motion map for both speeds remember motion map arrows to

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scale we need to jog your memory go check out the previous lesson that's

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also where we learned how to do displacement versus time graphs and

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velocity versus time graphs too so why don't we do those too if we have a

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favorite graphing program go ahead and use that or rock it old-school with

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graph paper and a pencil put both fast and slow data on the same graph that'll [Displacement v time graph appears]

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make it easier to compare them if we've done everything right the displacement

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versus time graph will have slanted lines and the velocity versus time will

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have horizontal lines and don't forget to title the graph, label the axes etc no

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shortcuts we're going the long way here ok awesome we've got a table of data

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we've got a motion map and graphs let's take a minute to think about what we've

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learned and ask ourselves some questions did the marbles roll at at constant

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velocity for the whole 5 meters was it easier to read the motion map or the [Questions appear on clipboard]

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displacement versus time graph looking at your displacement for his time graphs

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what is the difference between your fast and slow plots what does this tell you

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where the velocities you calculated for the different trials about the same and

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what could cause a difference in those how much faster was the fast velocity

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over the slow one is this what you expected?

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why or why not? And last but not least what went wrong in the

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experiment and what worked really well are you feeling really ambitious you [Man looking excited]

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want to be a full-on real-life scientist science isn't about just doing math

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drawing graphs and rolling marbles all over the place a good piece of science

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needs a good lab report to put it all together so let's look at what goes into

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a lab report and if you're feeling like a science superstar you can write one up [Boy band playing on stage]

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on your own for this marble lab first we've got a heading that's going to have

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your name your partner's names if you had any and your teachers names any

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stuff that would help the report get back to you if it ended up being in the

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lost and found any report needs a title get creative call it losing my marbles [Title of report appears on page]

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or the rolling marbles of time or just be boring and call it marble lab then we

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want to write an abstract say what the experiment was meant for give a brief

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description of how you did it and then a quick wrap-up of the results this is a

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short summary about 200 words give or take then we can tackle the official

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intro this is where we set the mood for the report kind of like lighting candles [Man in a bath tub]

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and putting on our Gregorian chants playlists explain why you are doing the

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experiment and what you are testing for and talk about the math that you'll be

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using everyone wants a warning when there's

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math ahead but don't go crazy here you want 400 words max then we have our

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materials and methods section this explains what you used in what you did

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with it did you have any problems any malfunctions this is the detail section [Materials and Method section points appear]

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try to keep it between 300 and 750 words Up next results here will show the data

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in a table or graphs or both just so happens to be a both huh if your data is

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pretty polished you shouldn't have to do a lot of explaining here so keep it

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short 50 to 250 words last is the discussion section you can cut loose

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with this gain any valuable insights to the secrets of the universe as the

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marble rolled on anything you took away that could apply to real life anything

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surprise you if you're stumped take some more time to think about the experiment

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as a whole and look we know that this is a big job now how many people write [Marble rolls on a desk]

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reports just for the fun of it and the people who do they're awesome and

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amazing and should be on a watch list somewhere not a bad list to be on

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