فيزياء الحركة والطاقة

Energy

• Definition: The ability to do work
• Types:
  • Kinetic energy (KE): energy of motion
  • Potential energy (PE): stored energy
  • Thermal energy: energy of heat
  • Electrical energy: energy of charged particles
  • Chemical energy: energy stored in chemical bonds
• Units: Joules (J)

Force

• Definition: A push or pull that causes an object to change its motion or shape
• Types:
  • Contact force: force exerted through physical contact
  • Non-contact force: force exerted through a distance (e.g. gravity, magnetism)
• Units: Newtons (N)
• Newton's Laws of Motion:
  1. Inertia: an object at rest remains at rest, an object in motion remains in motion
  2. Force and acceleration: F = ma (force equals mass times acceleration)
  3. Action and reaction: every action has an equal and opposite reaction

Acceleration

• Definition: The rate of change of velocity
• Units: meters per second squared (m/s^2)
• Calculated using: a = Δv / Δt (acceleration equals change in velocity divided by time)
• Related to force: F = ma (force equals mass times acceleration)

Work

• Definition: The transfer of energy from one object to another through a force applied over a distance
• Formula: W = F × d (work equals force times distance)
• Units: Joules (J)
• Types:
  • Positive work: force and displacement are in the same direction
  • Negative work: force and displacement are in opposite directions

Velocity

• Definition: The rate of change of an object's position
• Units: meters per second (m/s)
• Calculated using: v = Δx / Δt (velocity equals change in position divided by time)
• Related to acceleration: a = Δv / Δt (acceleration equals change in velocity divided by time)
• Types:
  • Instantaneous velocity: velocity at a specific moment
  • Average velocity: velocity over a period of time