00:01
In this problem, we have a long jumper with a mass of 75 kilograms who takes three and a half second, no, three in one tenth seconds, to reach a speed of 10 meters per second.
00:24
And we're wondering what is the power output.
00:28
So the change in kinetic energy would be the work.
00:40
And the initial kinetic energy is zero.
00:44
So the final kinetic energy is one -half times mass, times v to the second power.
00:52
One -half times the mass, which is 75 kilograms, times v to the second power, that would be 10 meters per second to the second power.
01:12
So we can calculate the work by just doing 10 to the second power, which is 100 times 75, and then dividing by 2.
01:25
So that's going to give us 3 ,750.
01:31
And we're talking about work here...