SPEED

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Speed is a measure of how fast something is moving. It is the rate at which distance is covered and is always measured in terms of a unit distance by a unit of time.

 
Speed= distance/Time

Average speed is:
Average speed= total distance covered/Time interval
Average speed = 320 km /4 h =80 km/h

If we know average speed and time of travel, distance traveled is easy to find. A simple rearrangement of the preceding definition gives
Total distance covered= average speed x time interval

ACTIVITY:
The physics teacher walked a distance of 12 meters in 24 seconds; thus, her average speed was 0.50 m/s. However, since her displacement is 0 meters, her average velocity is 0 m/s. Remember that the displacement refers to the change in position and the velocity is based upon this position change. In this case of the teacher’s motion, there is a position change of 0 meters and thus an average velocity of 0 m/s.

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