An object moves, along a line, from point A to B to C and then back to B again as shown in the figure below in half an hour.
a) find the average speed of the moving object in km/hr.
b) find the magnitude of the average velocity of the object in km/hr

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a). Average speed = 26 km per hour

b). Average velocity = 10 km per hour

Explanation:

a). Distance between A to B = 5 km

    Distance between B to C = 4 km

    Total distance traveled between A to B to C and then back to B

    = 5 + 4 + 4

    = 13 km

Time taken to cover this distance of 13 km = an hour

Therefore, average speed during this trip =

                                                                      = 26 km per hour

b). Average velocity =

   Displacement = (Distance between A to B) + (Distance traveled between B to C) - (Distance traveled from C to B)

                           = 5 + 4 - 4

                           = 5 km towards A

Average velocity =

                             = 10 km per hour

that tool is called an altimeter which measures your altitude which can be used to tell which atmosphere you are currently in, including the stratosphere.

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