Is Velocity Zero if Displacement is Zero?

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James walks 2 km away from home and then returns, resulting in a total displacement of zero. His average speed is calculated as 1.11 m/s, while his average velocity is zero due to the net change in position being zero. The discussion highlights that if displacement is zero, average velocity is always zero. Additionally, instantaneous velocity can vary at different points along the path, even when average velocity is zero. Understanding these concepts clarifies the relationship between displacement and velocity.
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James walks 2 km away from home in 30 minutes. He then turns around
and walks back home along the same path, also in 30 minutes. Calculate James’
average speed and average velocity.

My answer:
s = d / t
= 4000m / 3600s
= 1,11 m.s -1

v = Δx / Δt
= 0 m / 3600 s
= 0 m.s-1I'm just confuse about one part in velocity, so if your displacement is 0 the velocity is always 0? yeah?
 
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Joseph Austin said:
I'm just confuse about one part in velocity, so if your displacement is 0 the velocity is always 0? yeah?
The average velocity is then zero. There is also the concept of instantaneous velocity which applies at any given instant anywhere along the path.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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