|Published (Last):||1 January 2014|
|PDF File Size:||19.80 Mb|
|ePub File Size:||1.1 Mb|
|Price:||Free* [*Free Regsitration Required]|
So what’s the area of this triangle? Once again when were are dealing with objects not too far from the center of the earth we can make that assumption. So this right up here is 13 meters per second. How do I calculate its area? Average the two, and then multiply that times the time that goes by.
The rock will have an initial velocity Vi of Acceleration of aircraft carrier take-off. So plus one half times our final velocity. But we have to be very careful with this.
Gennemsnitlig hastighed for konstant acceleration (video) | Khan Academy
If we’re already going five meters per second. Eight meters per second. What are the kinematic formulas? That is the area of this right here.
So, we have the acceleration due to gravity. And let’s say that we have a constant acceleration. So you multiply how much time passed times acceleration. Because of this convention here, we know it is to the right.
And then plus– what do we have to do– we have the change in time, once again, we have the change in time, times this height.
Gennemsnitlig hastighed for konstant acceleration
What are the kinematic formulas? So anything minus half of it, you’re just going to have a positive half left. And all of that is being multiplied by our change in time. But the only reason why I can just take the starting velocity and the ending velocity and, adding them together, and then divide by two. Once again, if we just think about the variables.
Gennemsnitlig hastighed for konstant acceleration. You might be saying “Wait, clearly the force of gravity is dependent on the distance. So every second that goes by– so after one second, I’m going to go two meters per second faster.
And now what does this simplify to? Let’s say that– and for the sake of this video just so I don’t have to keep saying this is the magnitude of the velocity, this is the direction of the velocity, et cetera, et cetera.
So if you factor out a delta t, you get delta t times, a bunch of stuff, v sub i. So your initial velocity. Little g is Well the final velocity is going to be your initial velocity plus your acceleration times change in time. Well I’m starting at five meters per second. Because it’s two meters per second, per second. All of this is what displacement is going to be. And what’s the height here? The distance that we travelled. Or it’s the change in velocity due to the acceleration.
Now I want to plot distance relative to time. If this was a curve or if the acceleration was changing, you could not do that.
And let’s simplify this a little bit. I can draw a straighter line than that. This is the purple area. It’s the arithmetic mean of these two numbers. And I want to take a pause here. Or this is the same thing as 13 meters per second, which is going to be our final velocity. And we can distribute the one half.
You can really view g as measuring the gravitational field strength near the surface of the earth.
And let’s say if I have a negative number, which we won’t see in this video, let’s assume that I’m going to the left. Kinematic formulas in one-dimension.