An object travels North at 2 m/s for 9 s and then travels South at 4 m/s for 5 s. What are the object's average speed and velocity?

1 Answer
May 7, 2016

"displacement="-2 m
"velocity="-1/7 m/s
"speed="19/7 m/s

Explanation:

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"displacement to the north direction: "v*t=2*9=18m
"displacement to the south direction:"v*t=4*5=20m

"displacement="-2 m

"velocity"=("displacement")/"time"

"velocity=(-2)/(9+5)

"velocity="-2/14

"velocity="-1/7 m/s

"speed="("distance")/("time")

"speed="(2*9+4*5)/(9+5)

"speed="(18+20)/14

"speed="38/14

"speed="19/7 m/s