Pulley Lab

                                                               
                                                                   Design:

In this lab, we built a pulley system in order to lift brass objects. Without using the pulley we determined that it required 2 Newtons to lift a 0.2 kg brass mass 10 cm, using the formula 10N/kg. We used a LabQuest electronic probe to measure Newtons while the pulley was being used. It was calculated that only 1.2 Newtons were needed to carry the same object to the same height. The length of our string was measured as 28 centimeters. Two bar graphs (with pulley and without pulley) were drawn to record our data. The x-axis was labeled "distance" and the y-axis was labeled "force." The graph measured area of a force and distance, (A=DF) becoming energy. Other related formulas are Work=(Force)(Distance) and Joules=(N)(M).

                                                                                        Reflection:


Because of this lab, we discovered the length of the string and the size of the pulley relates to the amount of force required on an objects. The longer the string and the larger the pulley decreases the Newtons needed to carry the brass mass. The graph proves that increased distance, leads to decreased force and vice versa. It is known as a trade-off or an inverse in mathematical terms.

                   

                                                                       Real-World Connection:

The pulley is one of the many simple machines that makes our lives easier. Cranes are important tools found in construction sites that implement a pulley-like system to carry tremendous objects. The pulley in our experiment was like a crane but at a much smaller scale.
                                                           

Fun Facts:

• Hero of Alexandria, an ancient Greek engineer and mathematician, identified the pulley as one of the six simple machines used to lift weights.
• A pulley is also called a sheave or drum.
• The definition of a pulley is "a wheel on an axle that is designed to support movement of a cable or a belt along its circumference."

Here is a  a video on youtube that explains how pulley systems work. Runs for about 3 mins.