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Motion: Distance and Displacement

Introduction to motion, scalars vs vectors, and the equations of motion.

Introduction to Motion

Motion is the change in position of an object with respect to its surroundings in a given interval of time.

Scalars vs Vectors

  • Scalar Quantity: Has only magnitude (e.g., Distance, Speed).
  • Vector Quantity: Has both magnitude and direction (e.g., Displacement, Velocity).
Concept Check:

If you move 3m East and then 4m North, what is your distance and displacement?

Distance: 3 + 4 = 7m

Displacement: √(3² + 4²) = 5m (Pythagoras Theorem)

Equations of Motion

For uniform acceleration 'a', initial velocity 'u', final velocity 'v', time 't', and displacement 's':

  1. v = u + at
  2. s = ut + ½at²
  3. 2as = v² - u²

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