Linear Motion

Linear Motion

1. Scalar quantities

   • Magnitude only
   • Examples
     • Distance (d)
       • How far one point is from another
       • Metres (m)
     • Speed
       • Distance travelled per unit time
       • Metres per second (m/s)
     • Mass
     • Temperature
     • Time (t)
       • Measures the duration of events
       • Seconds (s)
     • Electric current

2. Vector quantities

   • Both magnitude and direction
   • Displacement (s)
     • Distance in a given direction
     • Metres (m)
     • The straight line distance between two points
       • Accompanied by the direction
   • Velocity (u or v)
     • The rate of change of displacement with respect to time
     • Average velocity = (u + v)/2
       • U = initial velocity
       • V = final velocity
   • Acceleration (a)
     • Rate of change of velocity with respect to time
     • Metres per second squared
     • (change in velocity) / (time taken)
       • (v - u)/ t
   • Other examples
     • Momentum
     • Force
     • Magnetic flux density

3. Equations of Motion

   • Linear Motion: Newton's Equations of Motion
   • v = u + at
   • s = u + (1/2)at²
   • v² = u² +2as

4. Graphs

   • Linear Motion: Graphs of Linear Motion
   • Distance-Time Graphs
     • Slope = velocity
   • Velocity-Time Graphs
     • Slope = acceleration
     • Area under the graph = distance travelled

5. Vector calculations

   • Linear Motion: Basic Vector Operations
   • Adding co-linear vectors
     • Same direction
       • Add magnitudes
       • Use same direction
     • Opposite direction
       • Subtract magnitudes
       • Use direction of larger vector
   • Adding perpendicular vectors
     • Pythagoras theorem
     • Sine, cosine, tangent
   • A vector can be resolved into two perpendicular component vectors