00:01
In this problem, we're given a mass of a hammer of 0 .45 kilograms, a initial velocity of 7 meters per second, and a distance that the nail travels into the board of 1 centimeter.
00:21
We can write that as 0 .1 meters.
00:27
And we want to calculate the duration of the impact.
00:30
Before we can do that, we actually need to do part b, which is the average boards exerted on the nail.
00:37
So we're going to do part b first.
00:40
So we need to apply the work energy theorem, which tells us that the work done is equal to our change in kinetic energy.
00:51
So we're going to have our final kinetic energy minus our initial kinetic energy.
00:59
And the force is going to be in the opposite direction so we can use an angle of 180 degrees or just negative 1.
01:12
So a cosine of 180 is negative 1.
01:14
And using the distance that we traveled, or the nail travel, the s -point -0 -1, to determine our force...