Feb. 4
Objectives:
• build a pulley of assigned number of supporting strings
• distinguish between direction of effort and resistance
• identify and draw correct number of supporting strings
• determine ideal mechanical advantage
Bell Ringer:
Draw the three kinds of levers. On each kind of lever:
(a) label (E, R, fulcrum),
(b) identify (I, II, III) the three lever types.
Lesson:
1) Review "Kinds of Levers" (worksheet from last class)
2) Introduce pulleys:
(a) names of pulley systems: fixed, moveable, compound or block and tackle,
(b) direction of effort and resistance forces,
(c) compare effort and resistance force magnitudes,
(d) identify which lengths of rope/string offer support to resistance and which do not,
(e) ideal mechanical advantage (IMA).
3) Distribute and together with students, complete Pulley Basics worksheet.
4) Distribute and assign for homework, Pulley Basic Practice worksheet.
Assignment:
1) Large quiz (over ALL work, torque and lever topics and assignments) next class.
