Electro-Online Video Lecture Notes

Overview:

• Focus on forces applied to a block.
• Discusses scenarios with vertical and angled forces.

Vertical Force Scenario:

• No horizontal forces acting: Block remains stationary.
• Friction force: Potential for maximum friction force exists, but actual friction force is zero without horizontal forces.
• Normal Force: Equals the reaction force.
  • Calculation: Weight of block + force applied on block.

Angled Force Scenario:

• Components of Force:
  • Vertical component contributes to weight.
  • Horizontal component causes friction.
• Normal Force:
  • Larger than just counteracting weight.
  • Sum of block's weight + y-component of applied force.
• Reaction Force:
  • Vector sum of normal force and friction force.
  • Friction opposes x-component of applied force.
• Diagram Explanation:
  • Showcases weight, applied force, and friction interactions.
  • Emphasizes vector sum of forces.

Maximum Friction and Motion:

• Maximum Applied Force in x-direction:
  • Block on verge of motion.
  • Friction force equals maximum static friction force.
• Force Balance:
  • Weight + y-component counteracted by normal force.
  • Friction force counteracts x-component of applied force.
• Reaction Force:
  • Vector sum with greater angle due to larger components.

Kinetic Friction Scenario:

• Block in Motion:
  • Friction force decreases due to kinetic coefficient of friction.
  • Angle of reaction force smaller due to smaller friction component.
• Calculation Changes:
  • Friction force = normal force × kinetic coefficient of friction.
  • Normal force includes weight + vertical component of force.

Key Takeaways:

• Difference between static and kinetic friction.
• Normal force influenced by vertical components of applied forces.
• Friction and normal force interactions highlighted in block motion scenarios.