funding for an audible paint course television was made possible in part by the College Board almost nobody can reason with you Mr Wares Cunningham McHugh the great founder itself and all other funding were made possible by viewers like you we forced you [Music] oh hello and welcome to another episode of the APC TV the mechanics Edition I'm your host Mr McHugh and today you'll be watching season one kinematics episode 2 kmeq I Choose You So objectives for today's video is be able to Define acceleration and its three cam eqs which is really content accelerated motion equations and to be able to differentiate between what an object is speeding up and slowing down so a quick recap to start this video acceleration is the rate of change in velocity it's how much your velocity is changing each second so yes it is a vector just like velocity is a vector and its most simple equation is a equals Delta V over T which is simply final minus initial velocity divided by time and units of meters per second squared and yes when you get a number you would include a Direction with that whether that's shown by positive and negative sign or that's shown by an East-West up down Etc and so we can solve acceleration problems using constant accelerated motion and Cam and cam equations or Cam eqs as I call it and that's pretty much all you'll hear me call it unless you want to say constant accelerated motion five times fast over and over great but I'm not going to do it I'm going to call it can and Kim is acceleration that is zero meters per second squared or some non-zero constant number hence the name constant acceleration or constant accelerator motion and there's three equations we use to solve these concepts are in motion or Cam problems equation one is the x equals x naught plus v naught t plus one half a t squared where X represents your final position X naught represents your initial position V naught is your initial velocity T is your time a is your acceleration and T is your time we also call this the no V equation because there's no final velocity present and so When selecting an equation to solve a candy Cube problem take that as a hint if they don't mention final velocity in the problem meaning it's not given it's not what you're solving for you run to this equation the no V equation or really how it's otherwise known as the position equation because you're solving for position X the second camera Q is V squared equals V naught squared plus two a Delta X where V is once again final velocity V naught is initial velocity a is your acceleration Delta X is your x minus X naught or your final minus initial positions you might know it as the no time or no T equation which again if you don't have time in a problem and you don't have the time to care about it then you use the No Time equation V squared equals V naught squared plus 2A Delta X or again that Delta symbol just means changing and last but not least you have V equals V naught plus a t which is actually where a equals Delta V over t comes from if you do just a little bit of algebra if you subtract over the V naught and call it Delta V or change and divide by time that's where that Good Old Reliable acceleration equation comes from but you use this equation when you don't have X this is the no X equation it's when we do not care about position it's the easiest one to use it's one you would like to use it's the simplest algebraically you can't always use it but if you don't care about position or displacement then you use this equation and this is the velocity equation that can be really helpful in solving for final or initial velocity and the last thing I want to talk about with Cam is when you're undergoing acceleration or constant accelerated motion when do you know if you're speeding up and when you know if you're slowing down speeding up bursts slowing down and I made this beautiful chart for you where if you have acceleration in the positive direction and you have velocity in the positive direction you are speeding up if you have acceleration in the negative Direction and you have velocity in the negative Direction you are speeding up and a lot of times we associate negative acceleration with slowing down we need to rewire how we think about it what speeding up means is that our velocity and acceleration are heading in the same direction so if you're moving at negative 5 meters per second so you're heading in the negative direction and you now accelerate in the negative Direction you're going to get faster and faster and faster in the negative Direction and you're going to reach some really big negative number so you got faster so whenever you have the same direction or same signs on your acceleration and velocity you know you're getting faster whether it's in the positive or negative Direction if your acceleration is positive and your velocity is negative you are slowing down and same if your acceleration is negative in velocities positive you are also slowing down because they're heading in opposite directions right so if you're running in the positive Direction at five meters per second and you decelerate or let's say you have an acceleration of negative two meters per second squared you will slow down until you stop you hit zero meters per second of velocity and you are to stop so since they're working against each other you you slow down until you eventually stop and then maybe you speed up in the other direction we don't know but that's the key if acceleration velocity are in the same direction whether that be positive or negative you are speeding up if acceleration velocity are in opposite directions you are slowing down so if you have any questions you can email me or leave them in the comments box below and otherwise have a fantastic night