Basic Physics Concepts

Overview

• Covers fundamental topics in physics:
  • Displacement
  • Velocity
  • Acceleration
  • Projectile Motion
  • Newton's Laws
  • Forces
  • Momentum

Distance and Displacement

• Distance:
  • Scalar quantity
  • Only has magnitude (e.g., 200 miles)
• Displacement:
  • Vector quantity
  • Has both magnitude and direction (e.g., 300 miles north)
  • Example: John walks 8 meters east, then 3 meters west
    • Total distance: 11 meters
    • Displacement: 5 meters east (final - initial position)

Speed and Velocity

• Speed:
  • Scalar quantity
  • Always positive
  • Formula: ( d = vt )
• Velocity:
  • Vector quantity
  • Can be positive or negative
  • Includes direction (e.g., 30 m/s west)

Acceleration

• How fast velocity changes
• Formula: ( a = \frac{\Delta v}{t} )
• Positive acceleration: speeding up
• Negative acceleration: slowing down

Gravitational Acceleration

• Earth's gravity: ( g = -9.8 \text{ m/s}^2 )
• Affects vertical but not horizontal velocity

Projectile Motion

• Motion under gravity's influence
• Horizontal component (( v_x )) is constant
• Vertical component (( v_y )) changes due to gravity
• Example scenarios: ball kicked off a cliff, thrown upwards

Newton's Laws of Motion

Newton's First Law

• An object at rest stays at rest; an object in motion stays in motion unless acted upon by a force.
• Force: push or pull action

Newton's Second Law

• Formula: ( F = ma )
• Example: 10 kg mass with 80 N force gives acceleration of 8 ( \text{m/s}^2 )

Newton's Third Law

• For every action, there is an equal and opposite reaction.

Conclusion

• Understanding these concepts is essential for a foundational grasp of physics and its applications.