Science of Technology

This tool allows you to raise a mass on a hinged plank, increasing its gravitational energy. Increasing an object's energy requires work. In each of the following tasks, the work can be completed with a larger or smaller force. What is the tradeoff?

• Lift the mass by pulling up on the zip-ties as shown.
• Compare the effort required to lift the mass using each zip-tie.
• Which makes it easier to lift the mass? Which requires more distance?

• Attach a string from the wind-up reel to a hook on the plank as shown.
• Compare the effort required to grip each wheel and spin it.
• Which makes it easier to lift the mass? Which requires more distance?

• Start two bolts (#10-32 and #10-24) in the t-nuts as shown.
• Compare the effort required to lift a mass using each bolt.
• Which makes it easier to lift the mass? Which requires more turns?

• Attach a string to a hook on the plank and over the hook on the vertical piece as shown.
• Thread the string under and over two more hooks and pull the string.
• Compare the effort required to pull the string when it is looks like a 'V' and when it looks like an 'N'.
• Which makes it easier to lift the mass? Which requires more distance?

• Consider starting your summary this way: “There are two ways to increase an object's gravitational energy. One way requires …”