Filipovic-Physics-2d-Force

Unit 2: Physics

Overview

  • Understanding motion and forces is critical in physics.

  • Key Concepts:

    • Force: A push or pull requiring energy if overcome by resistance.

    • Work: Energy expended increasing speed or moving an object against an opposing force.

Newton's First Law of Motion

  • States that an object will remain at rest or in uniform motion in a straight line unless acted upon by a net external force.

  • In the absence of resistive forces, motion at constant speed requires no energy input.

Forces

  • Definition: A force is the interaction that results in a push or pull on an object.

    • Occurs when two objects interact.

    • Forces exist only during the interaction between objects; they cease once the interaction ends.

Types of Forces

  • Contact Forces: Occur when two objects are in physical contact.

    • Examples include:

      • Friction

      • Tension

      • Normal

      • Applied

  • Non-Contact Forces: Act at a distance without physical contact.

    • Examples include:

      • Gravitational

      • Electromagnetic

      • Nuclear

Measurement of Force

  • Unit of Force: Newton (N)

    • Defined as the force required to accelerate 1 kg mass at 1 m/s².

    • Relation: 1 N = 1 kg·m/s²

Concepts of Motion and Forces

  • Balanced Forces:

    • Forces acting on an object are equal in size and opposite in direction leading to no motion change.

    • Example: Object remains at rest or remains in uniform motion.

  • Unbalanced Forces:

    • Forces acting on an object are not equal, causing motion to change (speed up, slow down, or change direction).

    • Acceleration is directly proportional to net force and inversely proportional to mass.

Free Body Diagrams

  • Visual representation to show all forces acting on an object. Helps in analyzing the net force affecting the object’s motion.

Applied Problems and Examples

  • Model Questions:

    • Practice scenarios involving balanced and unbalanced forces, where forces are applied on surfaces with friction.

Summary and Learning Check

  • The ability to explain motion under the influence or lack of forces is key to understanding gravitational potential energy and work in further studies.

  • Assessments will derive from learning concepts covered in this unit.