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Intro2 homework help

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okay honey this is the little homework help with intro to see a little bit about the directions a person start riding a bike away from the starting point on a straight path moving at constant speed so that means we don't know what the speed is that we're just giving it a Forno for 10 and a timer 5 SEC then stops for 10 seconds then move forward at a constant speed b360m and a timer 15 seconds we have time stop again for 10 seconds then move forward at a different kind of species 30 m in a time of 5 today and stopped again currents around so go in the other direction we're going to have to somehow find a way to deal with that and return to the starting point in 25 seconds at another car so first of all one make a position versus time graph of this situation so we have a grid down here that we are going to grab the stuff it's a position versus time position and distance for us in this class are pretty much interchangeable the small difference between them that position is really kind of like disappointment instead of distant that will come in a later Physics course I want to see the basics down I do is we're going to say the person is there a time I'm starting at 0 meters and then if we go back and read it says moves 10 m in a time of 5 Seconds 25 50 75 and down here are the time so there's one two three four five six seven eight nine 10 that means every two is worth alkyd label this one is five if I wanted to you don't need to 10 15 20 25 and you see it's consistent down here so first thing is in a time of it moves 10 m 10 meters in a time of 5 Seconds and then stops for 10 seconds so it stays at 10 four five 10 seconds up to 15 seconds now if you want to we can start connecting these I usually wait till the end but using a straightedge because all these are constant speed so we need constant that is online for our first motion of this bicycle trip there's our second note slope no speed same as a distance time graph to position time graph neck then moves Ford 460 okay we're already at 10 if we go 60 more we're going to be up here at 70 so we're going to be up to 70 and in a time of 15 seconds since when party at 15 seconds 15 more is going to be 30 here's where I like to use my ruler so I lose my line when I'm looking up sometime I know now that this line is my 30 line so I can go up there and get up to 70 there are seventy right here or next datapoint code right in that location so we're doing what's called a line graph in this one. If you connect those now he can or we can wait till later so now we're 70 Mi away from the starting and it's 30 seconds into our trip and then it says stopped again for 10 seconds so that's going to be another 2 blocks by 10 seconds with no slope for no speed next move forward again at a conference tc30 more me so step in 30 we're going to be up to a hundred in 5 seconds we are at 42nd so we're going to be at 45 seconds so 5 Seconds more than 45 Amber way up here to a hundred and then stops again for 10 seconds it bad enough. No float defeat 10 seconds of going to be on this graph indicated by two blocks 4250 is 10 seconds then to block now this is where it gets tricky this is why some people read this and say turn around and returns to the starting point some people will try to connect this back here which means you're going backwards in time you can't go backwards in time figure it out I don't think anybody has very few people know about it starting point is 0 meters so here we are at 40 10 seconds later 55 seconds and it says in a time of 25 seconds so 10:25 or maybe write out the 80s and it says returns starting position starting point so the starting point right here so this is the last line it goes down like this you might notice that when you turn the other direction your sloped becomes downhill or negative that's something we're going to start getting to in this poor so now we can label it a b c and d are different parts second Vine constant speeds a b c and d by showing a slope determination by showing slope determinations here so first of all I'll do a and then all the rest are going to be done the same way with a we're going to pick two points do you smoke the weed label though I'm going to take this beginning point which is 0 second 0 meters and then this point right here which is 5 Seconds 10 meter those are the two points I'm going to use for my slope for a so now I write up here and equals Y2 - y1 / X-2 - X1 always start with that every time I know it seems repair what is the nature sign so now we've got our points down here why to is 10 Mi y1 is 0 meters X2 is 5 Seconds answer in X1 0 seconds so then 10 - 0 is 10 calculator if I wasn't real comfortable doing this in my head but I am 10 / 5 is too and we have a meter per second so there's my slope Nation now I know that this bicyclist is going at a speed of 2 meters per second which is about once you learn to convert you'll find out that's about 5 miles an hour okay so now we're going to repeat the same thing except you got to get your stuff green coordinate in your ending cord so here this is now it's 15 seconds and meter that's our X and Y X1 and y1 for lying be and then 2B X2 + Y2 for line be so where is this we are at 30 seconds and 70 m so now again you will go ahead and you'll do em now we're doing another Emily's can get confusing so since we are finding speed a here we might do em with a subscript a you figure out what we put here that's cool and then when you do the third float maybe MC and LaFleur in the last one MD Now the one thing and always start with this this should be written written written bralette he's Y2 - y1 it's not a waste of time is physics so now continue with these with d this is a negative slope you should get a negative speed speed in physics never really negative it's really would be called something else is called Pollock City so don't worry about the little things in physics Social Work themselves out later just worried about understanding that this is negative or a downhill flow so the negatives is going to mean something with the speed if you didn't figure it out already positive mean we're moving away from our starting point is One Direction and then the removing back in the other direction just like a number line when you have zero in the middle and if you start going this way and it's 1 2 3 4 going this way it's also 1/2 34 but this is the other direction so we put this symbol to mean other direction negative in here you're going to have to get used to that negative numbers are not less than positive number they mean the other direction negative if you walk -1 or if you walk 1 mi you walk the same distance is this isn't Les it's just the other way okay so I think you can finish this up so good luck with that we'll check it when you get to class and see how successful you were good luck and go physics

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