Uniform circular motion particle problem

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The problem involves a particle in uniform circular motion with given acceleration vectors at two different times. The first acceleration vector is a1=(6m/s²)i+(5m/s²)j and the second is a2=(5m/s²)i-(6m/s²)j, indicating a change in direction but constant speed. The period of motion is more than 1.00 s, and the relationship between acceleration, radius, and angular speed is crucial for finding the radius of the circle. The discussion highlights confusion regarding the integration of velocity, the angles between acceleration vectors, and the overall approach to solving the problem. Understanding the relationship between centripetal acceleration and the radius is essential for determining the radius of the circular path.
EngnrMatt
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Homework Statement


At t1 = 3.00 s, the acceleration of a particle moving at constant speed in counterclockwise circular motion is

a1=(6m/s2)i+(5m/s2)j

At t2 = 4.00 s (less than one period later), the acceleration is

a2=(5m/s2)i-(6m/s2)j

The period is more than 1.00 s. What is the radius of the circle?

Homework Equations



T= (2∏r)/v
a=v2/r

The Attempt at a Solution



I drew out the vectors, but that's all I could do with the problem. Maybe I'm supposed to integrate to find velocity or something? I just really don't understand where to start. If I knew that, I could probably finish it up. But there's so much information given in the book for circular motion, I don't know what to do with it.
 
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What angle the acceleration vectors do enclose? What can be the total time period? What is the magnitude of the acceleration? How is the acceleration related to the angular speed and radius of circle?ehild
 
I don't know whether I'm supposed to find the angles of the individual vectors or average the acceleration over the given time period then find that one angle. And once that's done, I don't know what do with that information either. I wish I had a better professor, all he does is prove equations during class. Never goes over any examples.
 
Try to answer my questions. That will lead to the solution. It is uniform circular motion. The acceleration is centripetal. The acceleration vectors are along the radii. What is the angular displacement of the particle from t1 to t2?


ehild
 

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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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