Question

An object travels North at `2 m/s` for `8 s` and then travels South at `3 m/s` for `2 s`. What are the object's average speed and velocity?

Answer 1

Average speed: `2.2 m/scolor(white)("XXXX")`Average velocity: `1 m/s "North"`

Explanation:

`"Distance traveled"`
`color(white)("XXX")="Distance traveled going North"+"Distance traveled going South"`

`color(white)("XXX")=2m/sxx8s+3m/sxx2s`

`color(white)("XXX")=16m+6m`

`color(white)("XXX")=22m`

`"Duration of travel"`
`color(white)("XXX")"Time traveling North" + "Time traveling South"`

`color(white)("XXX")=8s+2s`

`color(white)("XXX")=10s`

`color(red)("Average speed")`
`color(white)("XXX")="Distance traveled"/"Duration of travel"`

`color(white)("XXX")=(22m)/(10s)`

`color(white)("XXX")=2.2 m/s`

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Displacement traveled (North)
`color(white)("XXX")="Distance traveled North" - "Distance traveled South"`

`color(white)("XXX")=16m-6m`

`color(white)("XXX")=10m`

`color(red)("Average velocity (North)")`
`color(white)("XXX")=("Displacement (North)")/"Duration of travel"`

`color(white)("XXX")=(10 m " North")/(10s)`

`color(white)("XXX")=1m/s " North"`