00:01
Suppose we have a force as a function of time that goes as 24t squared i -hat plus 6t j -hat minus 12t k -hat and the particle has a mass of four units, whatever those are.
00:20
And we're told that the initial position of the particle is negative two j -hat and the initial velocity of the particle is six i -hat.
00:29
So we wanna find the velocity as a function of time.
00:34
So first let's find the acceleration.
00:36
This will just be of course the force divided by the mass.
00:40
And so this will be 6t squared plus three halves, i'm sorry, i -hat plus three halves t i -hat minus 3t k -hat.
00:52
So the velocity as a function of time is gonna be the integral of a dt plus the initial velocity.
01:00
This, so this will be 2t cubed plus six i -hat and then plus 3 4ths t squared j -hat minus three halves t squared k -hat.
01:20
And then the position as a function of time is gonna be the integral of the velocity as a function of time plus the initial position.
01:29
So this is going to be, let's see, two, sorry, one half t to the fourth plus 6t i -hat and then plus one fourth t cubed minus two j -hat and then minus one half t cubed k -hat...