Speed, Displacement, and Velocity

Time

SI Unit: Seconds (s)

  • Scalar quantity

Time Intervals

  • Minutes

  • Seconds

  • Milliseconds

  • Hours

  • Days

  • Years

Measuring Time

  • Stop Watch

  • Stop Clock

  • Electronic Timer

Distance

SI Unit: Metre (m)

  • Scalar quantity (s or d)

Measuring Distance

  • Vernier Callipers

  • Micrometer Screw Gauge

  • Metre Stick

Speed

Rate of change of distance with respect to time.

SI Unit: Metre per second (m s-1)

  • Scalar quantity

Average‎‎‎‎⠀Speed=\frac{Dis\tan ce⠀Travelled}{Time⠀Taken‎}

Displacement

Distance in a given direction.

SI Unit: Metre (m)

  • Vector quantity

Velocity

Rate of change of displacement with respect to time.

SI Unit: Metre per second (m s-1)

Average⠀Velocity=\frac{Displacement⠀Undergone}{Time⠀Taken}

Constant Velocity

When an object moves in a straight line and does not speed up or slow down.

Distance Time Graph

A graph showing how the distance of an object from a given point varies with time.

  • Slope of the graph is the speed of the object.