Hello everyone, welcome to another day of LEGO challenge. It is the third class of the semester and good to see everyone showed up. This week, we build a hammer. Yes, we are going to knock something hard. The building process is not hard, most of the students finished right after half of the class time and go on knocking. For the experiment, we are going to test the friction on different gears. First we test it out by hands and give it a rating of how much force we use to push an axle through it from 1-4. Then we use our hammer to count how many time it takes to knock the axle through. At this point, we have an idea of how much friction it has on each gears. The second part of the experiment is to test does the angles, which is how much the hammer lift, effect the force to knock? This would be their homework and I’m willing to discuss about it on the following week.