00:01
In this question, we're given a force versus time graph, and we're told that a 5 -kilogram object that is initially at rest is subjected to this force, and we're asked to find the object's velocity at t equals 6 seconds.
00:18
So first, let's recall what we know about graphs and finding an object's velocity.
00:25
So remember that the area under an acceleration time graph would give the total change in velocity.
00:43
But we have force time.
00:46
So we need to ask ourselves, how do we go from force time to acceleration time? and we know that force and acceleration are related very intimately through newton's second law, right? f equals ma.
01:06
And so we can convert this force time graph into an area time graph just by dividing by mass, right? because if force is equal to m times a, then a is equal to f divided by m.
01:20
So instead of having a maximum value of 10 newtons, we have a maximum acceleration of 10 newtons divided by 5, 2 meters per second squared, right? so where we saw the maximum value of f is 10 newtons, that means that the acceleration, the maximum acceleration, this object experiences is 2 meters per second squared.
01:56
So we don't really need that for the question.
01:59
I'm just making the point that we can convert these forces into accelerations very easily.
02:05
So what we need to do is bearing in mind that we're dividing the y values by five for the mass, we need to just calculate the area under the curve...