During we test our Atwood’s machine, we asked to control the time between two weight to touch the ground in 2 second. However, it is really difficult to have difference time in 2 seconds in the real life ever we calculate to get the true mass of weights. There are two causes that we think may affect our margin of error which is the friction and the human benchmark. The friction always is the main issue of any experiments. In the lab, the friction still affect the experiment a lot. There are two different frictions affect our Atwood’s machine which is the air frictions and frictions of pulleys. In the dictionary, the air friction is the force that in the opposition to the relative motion which is act on the object as it passes though the air. (What is air …show more content…
During the calculation, the force net, people usually ignore the air friction, because the air friction is too small and it usually does not affect the result a lot. However, it is existing in the real life for sure, because when our group test our Atwood’s machine in the normal classroom, the classroom is full of the air ever we close all of the windows and doors. In this experiment, the weights fall down to the ground, and the air friction is slowing it down looks like the barriers (Diagram 1.1). This is the first friction which affect the experiment to have the margin of error not so much but it still will affect. Frictions of pulleys is more effective than the air resistance. The bearings of the pulleys have the friction. The way to improve the pulleys have the friction is when nothing is on the pulleys, people rotate the pulleys and leave it alone. Based on the Newton’s First law which is “In an