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A dog walks 10 km north in 2 hours and then 8 km south in 1 hour.

a) What is the dog’s average speed for the whole journey?

b) What is the dog’s average velocity for the whole journey?

User LINGS
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1 Answer

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Answer:

Average speed = 6 km/h and Average velocity = 0.67 km/h

Step-by-step explanation:

Given that,

A dog walks 10 km north in 2 hours and then 8 km south in 1 hour.

(a) Average speed = total distance traveled divided by total time taken

Distance = 10+8 = 18 km

Total time = 2+1 = 3 h

Average speed = (18/3 )km/h= 6 km/h

(b) Average velocity = net displacement divided by total time taken

Let north is positive and south is negative

Displacement = 10+(-8) = 2 km

Total time = 2+1 = 3 h

Average velocity= (2/3 )km/h= 0.67 km/h

User Fissure King
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