Post created by: Josh
It was 3:00 PM in the afternoon the day my physics in popular media assignment was due and I was really struggling to find something to write my assignment on. My brain was blank, and the only thing on my mind was food so i decided to go on YouTube to clear my head and relax. Then all of a sudden my favorite personal trainer posted a new video so I clicked on it. It was a video for proper bench press form. Then it finally hit me. I pondered on how much force he needed to lift the weight he was lifting (225b lb). In order to solve this problem, I first needed to convert pounds to kilograms which came out to 102 kg. Then I needed to find out the acceleration at which he lifted the weight which is change in velocity over change in time. The concentric portion of the lift took 2 seconds and velocity is estimated to be about 0.7m/s. This is 0.7/2 which is equal to 0.35m/s^2. Multiply this by 102 and you get 35.7 N.
Comments