00:01
In this question, we are constructing a motion diagram for an object that starts from rest and speeds up, then has constant velocity, and then slows back down to a stop.
00:13
And so a motion diagram is going to consist of dots for the position of the object, and then velocity vectors, or velocity arrows, at each point, and then we're also going to have delta -v arrows between the velocity arrows.
00:51
So the positions for an object speeding up are going to start off close together, and then gradually get further apart, because speeding up, of course, means traveling a greater displacement each second than the second before.
01:17
And then we're going to reach a point where we have constant velocity, and our dots become equally spaced, because constant velocity means traveling the same displacement each time interval as the time interval before.
01:36
In this case, we're going to call it one second.
01:40
And then, to slow down, our dots are going to get progressively closer together, because slowing down means traveling less distance each second, or each time interval, than in the one before.
02:01
And actually, i'm going to go ahead and pull maybe one more, a little bit closer.
02:08
Okay, so i've used blue to represent my speeding up.
02:17
And let me see, i think it was here that we're going to say...
02:24
And then it was out to here that we had constant velocity.
02:36
And then it was just for the last few dots that i had slowing down.
02:52
Yeah, okay.
02:53
And so now, we put a velocity arrow at each dot, and so our velocity arrows...
03:08
I'm not going to label every one with velocity v, because that's just going to get so cluttered.
03:15
But what we want to show is that our velocity arrows get longer when we're speeding up...