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3 years ago

I need help in this pls i really need a answer

Physics

1 answer:

IrinaK [193]3 years ago

3 0

Answer:

In terms of distance, average speed is 20 km/h

In terms of displacement, average speed is 0 km/h.

Explanation:

Total distance:

$= (40.0 - 10.0) + (20.0 - 10.0) + (40.0 - 20.0) \\ = 30.0 + 10.0 + 20.0 \\ = 60.0 \: km$

Total time is 3.0 hours

but:

$average \: speed = \frac{total \: distance}{total \: time} \\$

In terms of distance.

substitute:

$average \: speed = \frac{60.0}{3.0} \\ \\ = 20 \: {kmh}^{ - 1}$

$displacement = ( - 30.0) + 10 .0+ 20.0 \\ = 0$

In terms of displacement:

$speed = \frac{0}{3} \\ \\ = 0 \: {kmh}^{ - 1}$

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