00:01
By work energy theorem, the mechanical energy of an object, thus all the work that is done on it, must be equal to its final mechanical energy.
00:08
In this problem, we have a block of mass 1 .5 kilogram, is moving with a speed of 4 meters per second, is going to hit a non -linear spring.
00:19
It's non -linear because the spring offers a resistance that is equal to k times s square, where k is spring constant and s is the amount of stretching or compression.
00:30
That the spring is that the spring experiences so as a result the object will will slow down and we wish to find its speed when the spring is compressed by 0 .2 meters so we recognize point 1 as the point when the block is about to hit the spring and point 2 is when the block has already compressed the spring by the set distance 0 .2 meters so let us first establish that mechanical energy is the sum of potential and kinetic energy.
01:07
So notice here that the problem does not indicate any height or any increase or change in the elevation so that there would be no change in the potential energy.
01:18
As such, the mechanical energy in this case will be in the form of kinetic energy.
01:23
So we say since no change in the height, there is no change in the potential energy.
01:29
As such your m will just be in the form of kinetic energy...