CHAPTER 8POWERCHAPTER LEARNING OBJECTIVESUpon completion of this chapter, you should be able to do the following:lDefine the term “power.”lDetermine horsepower ratings.It’s all very well to talk about how much work aperson can do. The payoff is how long it takes him orher to do it. Look at the sailor in figure 8-1. He haslugged 3 tons of bricks up to the second deck of the newbarracks. However, it has taken him three 10-hourdays—1,800 minutes-to do the job. In raising the6,000 pounds 15 feet, he did 90,000 foot-pounds (ft-lb)of work. Remember, force x distance = work. Sinceit took him 1,800 minutes, he has been working at90,000 ÷ 1,800, or 50 foot-pounds of work per minute.That’s power—the rate of doing work. Thus, poweralways includes a time element. Doubtless you could dothe same amount of work in one 10-hour day, or 600minutes. This would mean that you would work at therate of 90,000 ÷ 600 = 150 foot-pounds per minute.You then would have a power value three times as muchas that of the sailor in figure 8-1.Apply the following formula:Figure 8-1.-Get a horse.8-1