Understanding Efficiency and Characteristics of Simple and Compound Machines in Science 8

Understanding Efficiency and Characteristics of Simple and Compound Machines in Science 8

• 1.
  Characteristics of EfficientSimple and Compound Machines Science 8 DepEd-style
• 2.
  Learning Competency • Explainthe characteristics of efficient simple and compound machines.
• 3.
  Objectives • • Defineefficiency • • Identify characteristics • • Distinguish simple and compound machines • • Apply concepts
• 4.
  Motivation • Compare pushinga box with and without wheels.
• 5.
  Review • Lever • Wheeland axle • Pulley • Inclined plane • Screw • Wedge
• 6.
  Machine • A devicethat makes work easier.
• 7.
  Simple Machines • Onebasic mechanical function.
• 8.
  Compound Machines • Combinationof two or more simple machines.
• 9.
  Examples • Bicycle • Scissors •Wheelbarrow • Can opener
• 10.
  Efficiency • Efficiency=(Useful Output/Input)×100%
• 11.
  100%? • Impossible becauseof friction and energy loss.
• 12.
  Characteristic: Reduce Effort •Requires less force.
• 13.
  Characteristic: Save Time •Faster completion of work.
• 14.
  Characteristic: Minimize Friction •Lubrication and bearings.
• 15.
  Characteristic: Durable • Strongmaterials and alignment.
• 16.
  Maintenance • Cleaning andlubrication improve efficiency.
• 17.
  Factors • Friction • Wear •Misalignment • Poor maintenance
• 18.
  Activity • Classify machinesand explain efficiency.
• 19.
  Applications • Home, school,agriculture, transport, industry
• 20.
  Think-Pair-Share • How cana bicycle become more efficient?
• 21.
  Summary • Efficient machinesreduce effort and energy loss.
• 22.
  Quiz • 5-item formativeassessment
• 23.
  Performance Task • Poster/Infographic
• 24.
  Assignment • Observe 5machines at home.
• 25.
  Thank You • Questions?