Circular motion — the acceleration is not constant?

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In circular motion at constant speed, the velocity is not constant due to continuous changes in direction, meaning that option (a) is false. Acceleration is present because it is directed towards the center of the circular path, contradicting option (b) that suggests constant acceleration. The net force cannot be zero since a centripetal force is required to maintain the circular motion, making option (c) incorrect as well. The confusion arises from the distinction between speed and velocity, as well as the nature of acceleration in circular motion. Understanding these principles clarifies that none of the statements provided are true.
JessicaHelena
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Homework Statement


An object moves at constant speed in a circular path. True statements about the motion include which of the following?

a) the velocity is constant
b) the acceleration is constant
c) the net force on the obj is 0 since its speed is constant

Homework Equations


hm none, really?

The Attempt at a Solution


the v is certainly not constant bc even if it's a UCM, direction is always changing.
There must be a centripetal force, so the net force cannot be 0.
I had rather confidently chosen that b) is the only true statement, but apparently none of them is supposed to be correct. Why is this so?
 
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Why do you think that (b) is correct?
 
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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