Finding angular velocity of a car and period of a planet's rotation

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The discussion revolves around calculating the angular velocity of a vehicle on a newly discovered planet with a mean radius of 4030 km and its relationship to the planet's rotation. The vehicle's speedometer reads 169 km/h, and it is noted that the vehicle's angular velocity is 5.28 times that of the planet's. The user has calculated the angular velocities but seeks confirmation on their accuracy and guidance on how to determine the planet's rotation period and the necessary speed for the vehicle to have an equal and opposite angular velocity. There is a concern about the correctness of the calculated values, as they do not align with the given relationship between the vehicle's and planet's angular velocities. The user expresses frustration over the lack of responses and seeks clarity on their approach to solving the problem.
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Homework Statement


Part a: A newly discovered planet has a mean radius of 4030 km. A vehicle on the planet's surface is moving in the same direction as the planet's rotation, and its speedometer reads 169 km/h. If the angular velocity of the vehicle about the planet's center is 5.28 times as large as the angular velocity of the planet, what is the period of the planet's rotation?

b: If the vehicle reverses direction, how fast must it travel (as measured by the speedometer) to have an angular velocity that is equal and opposite to the planet's?


Homework Equations



ω = (tangential v)/R

T = 2∏/(ω)

The Attempt at a Solution



I have found that the angular velocity of the car is .0397 rad/h, and the angular velocity of the planet is .0075 rad/h (please confirm whether these values are correct!). For part a, what should I plug in as my ω to find the period of the planet's rotation? For part b, how do I set it up to find tangential v?
 
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Hm, a strange lack of response. Is my question worded weirdly? I guess I'll have to solve this problem by myself.
 
Perhaps you could detail the work you did to find the results that you've stated in your first post. To me they don't appear to be correct. In fact they don't agree very well with the stipulation that ωv = 5ωp (where v → vehicle; p → planet).
 
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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