Speed
- Speed is defined as the rate of change in distance. It is a measure of how fast the distance change in a movement.
- Speed is a scalar quantity.
- The SI unit of speed is m/s (metre per second)
Equation of Speed
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Velocity
- Velocity is define as the rate of displacement change. It is the measure of how fast the displacement change of a moving object.
- Velocity is a vector quantity.
- The unit of velocity is m/s (metre per second)
Equation of velocity
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Positive or Negative Sign of Velocity
- In velocity, the positive/negative sign indicates direction.
- You can take any direction as positive and the opposite as negative.
- For a linear motion, normally we take the motion to the right as positive and hence the motion to the left as negative.