# Why would you use a single fixed pulley to lift a box if the mechanical advantage of the pulley is 1?

The pulley and rope together can be used to "change direction" of forces. In this case to lift, say, a box of books with your arms can be a little bit difficult. Using a rope and a pulley you can hang from one end using your weight to do the job for you! so basically your Weight (force ${W}_{1}$) is changed by Tension (force $T$) in the rope to lift the Weight ${W}_{2}$ of the box!!!!