00:01
Hi there, so for this problem, we have a block with a mass of 1 .40 kilograms and that is attached to a spring and it's a frictionless table which is at a high age of 4 meters above the floor.
00:12
The spring is compressed a distance that is given the distance of 0 .11 meters initially.
00:19
If the spring constant is also given, so the spring's constant is 6 ,000 newtoms per meter.
00:26
The question is, what is the speed of the block when it lifts the spring? so we need to find that final speed for this.
00:32
Initially, we consider that the initial speed of this block is going to be zero.
00:37
So the potential energy of the spring equals to the final kinetic energy of this block, right? since we are not changing in here for the height, so for the spring, the potential energy is 1 divided by 2 times the sprims constant times the elongation that in this length.
00:56
The case we label as the and that to the square, this is equal to the final kinetic energy, the kinetic energy, which is defined as one half of the mass times the final speed squared.
01:06
Now what we need to do in here, we can cancel this with this.
01:09
Remember that what we need to determine is the final speed.
01:14
So the final speed is the kinetic, the spritus constant divided by the mass times the distance d, we take the score root of this.
01:21
So we can take the distance d out of the score root...