A car moved 20 km East and 60 km West in 2 hours. What is its average velocity?
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Velocity is a vector with both magnitude and direction. The average velocity is the magnitude of the final displacement divided by the total time.
In this case the total displacement (the distance from the starting point to the end point) is 40 km so the average velocity is 40km/2 hours West or 20 km/hour West.
Speed is a scaler quantity and the average speed would be the total distance traveled over the total time. In this case the total distance traveled is 80 km so the average speed is 80 km/2 hours of 40 km/hour.
By inspection you can see that the average velocity will always be less than or at best equal to the average speed.
In this case the total displacement (the distance from the starting point to the end point) is 40 km so the average velocity is 40km/2 hours West or 20 km/hour West.
Speed is a scaler quantity and the average speed would be the total distance traveled over the total time. In this case the total distance traveled is 80 km so the average speed is 80 km/2 hours of 40 km/hour.
By inspection you can see that the average velocity will always be less than or at best equal to the average speed.
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60-20=40 km because velocity is displacement
Average=total distance/ total time
= 40km/ (2x3600seconds)= 0.005 km per sec or 5.5 meters per second
Average=total distance/ total time
= 40km/ (2x3600seconds)= 0.005 km per sec or 5.5 meters per second