This weekend, I went the Punahou Carnival and saw a lot of physics. The ride called the ring of fire is a ride that takes you in a loop. It slowly speeds up until you only have enough speed to make a full revolution. This ride reminded me of centripetal force. The equation for Fc=mass times velocity squared over the radius of the circle. The roller coaster feels normal force from the tracks and that helps the centripetal force. At the highest point at the slowest speed the normal force of the track is zero.

In this picture there are two different sized wrenches. If you want to maximize the amount of torque you can produce, you would want to use the longer one. In the equation lever arm times the force equals torque, if you increase the lever arm you can increase the torque. That’s why it is easier to loosen a bolt with a long handle than a short handle. If you need more torque on a bolt, all you need to do is lengthen the lever arm.