Rotational kinematic equations help

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SUMMARY

The discussion focuses on calculating the distance traveled by a point on the edge of a wheel with a diameter of 60.0 cm, which accelerates uniformly from 245 rpm to 395 rpm over 7.5 seconds. The correct approach involves using rotational kinematic equations, specifically the formula for angular displacement. The user initially calculated a distance of 125.66 cm but sought clarification on the methodology. Referencing a previous thread, the user is encouraged to model their work after established examples to ensure accuracy in their calculations.

PREREQUISITES
  • Understanding of rotational kinematics
  • Familiarity with angular velocity and its units (rpm)
  • Knowledge of the relationship between linear and angular displacement
  • Basic algebra for solving equations
NEXT STEPS
  • Review the derivation of the rotational kinematic equations
  • Practice converting between angular velocity (rpm) and linear velocity
  • Explore examples of angular displacement calculations
  • Learn about uniform acceleration in rotational motion
USEFUL FOR

Students studying physics, particularly those focusing on rotational motion, as well as educators looking for practical examples of applying kinematic equations in real-world scenarios.

bosox3790
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A wheel 60.0 cm in diameter accelerates uniformly from 245 rpm to 395 rpm in 7.5 s. How far will a point on the edge of the wheel have traveled in this time?

I keep getting 125.66, I don't really understand what forumal to use.
 
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Show what you did to arrive at your answer.
 
Check out this thread from the last couple of days where the rotational kinematic equations were used by another student. Model your work after that poster's work. Show all the relevant equations, and then show your algebra and how you get to the answer.

https://www.physicsforums.com/showthread.php?t=148047
 
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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