Doors

My door, the gateway to the wonderful place where I get to do my endless amounts of homework and sleep every now and then...I realized that this door I use everyday demonstrates torque and rotational motion. When I turn the doorknob to open the door, my hand exerts a torque on the doorknob, causing it to move in a circular path. When I push the door open, the door is moving in a circular path with the axis of rotation going vertically through the two hinges. This circular motion is due to the torque I exerted on the door, which is equal to rFsintheta. Therefore, if the doorknob was closer to the axis of rotation, the radius would be shorter, so the door would be harder to open because the torque exerted on the door would be less even if I pushed on the door with the same amount of force. This idea is demonstrated at Forever 21 because the doors of the dressing rooms each have a huge doorknob right in the middle of the door. I found that these doorknobs are not very effective because in addition to the fact that they don't turn, it is harder to open the door when pushing on these huge doorknobs instead of just pushing on the edge of the door opposite of the hinges. Such impractical, physics-ignorant decorations...