00:01
Alright, so we have a block that is sliding down a ramp, and then on a horizontal surface it hits a spring.
00:12
And we want to know how much the spring is compressed by.
00:16
So we're told a few different things here.
00:20
The mass is equal to 0 .4 kilograms for the box, and then we're told that it starts from rest, so the initial is 0 .4 kilograms.
00:35
And then we're told that the spring constant is 300 newtons per meter.
00:45
And then we're told that at a height of 1 .5 meters, the velocity is 2 meters per second.
01:02
Okay, and so we want to know how much this is compressed by.
01:11
So this will be x.
01:16
And so let's, we want to use conservation of energy here, but we have to pick two different points where we know the energy and compare those.
01:27
So at a height of 1 .5 meters, we'll call that right here.
01:32
Since we know it's not at the top, because it starts from rest.
01:35
So we'll say this is 1 .5 meters, and then that means at that point, this velocity is 2 meters per second.
01:46
So this is one point in which we can say we know the potential energy of the block and the kinetic energy because we know the height and we know the velocity...