The Turn of the Screw *
*Note: This is an abbreviated Project Idea, without notes to start your background research, a specific list of materials, or a procedure for how to do the experiment. You can identify abbreviated Project Ideas by the asterisk at the end of the title. If you want a Project Idea with full instructions, please pick one without an asterisk.
Abstract
How much force is required to advance a lag bolt (large wood screw with a hex-shaped head) into a piece of wood? You can measure the force by using a spring scale attached to the handle of ratchet. Pull on the spring scale until the bolt starts to turn, and note the required force from the spring scale. There are many potential experiments you could try. Think about answering the following questions: How does the force change as the bolt advances deeper into the wood? Why? How does the required force change as the diameter of the pilot hole is changed? Why? Can you change the required force by rubbing the bolt's threads with soap or wax? (Coyle, 2005)Share your story with Science Buddies!
Last edit date: 2013-01-10
Bibliography
Coyle, C.P., 2005. "Some Variables Affecting the Torque Required to Turn a Screw," California State Science Fair Project Abstract [accessed April 18, 2006] http://www.usc.edu/CSSF/History/2005/Projects/J0205.pdf.Share your story with Science Buddies!
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