Activity Four: Pulleys WD Simple Machines Activity Four: Pulleys

Essential Questions Do all pulleys operate the same way? WD Do all pulleys operate the same way? Does it matter how the pulley is set up? How should you use a pulley to maximize its effectiveness?

Goals Identify the effort force, the pulley (as either fixed or moveable), and the resistance force in pulley systems. Investigate the effect of using fixed and moveable pulleys on the effort force, effort distance, and the mechanical advantage of a pulley system. Distinguish between a mechanical advantage and a directional advantage. Collect data and draw conclusions about the collected data. Investigate the effort force & effort distance relationship in pulleys.

Main Ideas WD A pulley is a simple machine where a grooved wheel is free to rotate about a fixed axis. Pulleys can be fixed or moveable. Pulleys can provide a mechanical advantage and/or a directional advantage. An inverse relationship exists between the effort force and the effort distance.

Main Ideas cont. WD The arrangement and size of the effort force, the resistance force, and the pulley arrangement affects the effectiveness of the pulley system and its ability to accomplish a task.

Vocabulary WD Fixed Pulley: Moveable Pulley:

What do I do? Read Activity 4 Reading Do Part A: Getting a feel for pulleys. Read: Making Sense of Simple Machines Cut and paste pulley diagram worksheet Do Part B Do Part C Do Part D Investigation Reflection Summary Applying what you have learned