How Do You Calculate the Motion of Rotating Objects in Physics?

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To calculate the motion of rotating objects in physics, various scenarios can be analyzed using specific formulas. For a baton twirler, the height reached by the baton can be determined using its angular speed and the number of revolutions. In planetary motion, the angular speed, tangential speed, and centripetal acceleration can be calculated based on the orbital radius and period. The centripetal acceleration ratio between different points on a rotating plate can reveal the relationship between the lengths of the sides of the rectangle. Lastly, the tangential speed and net force acting on a star in a galactic orbit can be derived from its mass and angular speed. Understanding these concepts is essential for solving problems related to rotating objects in physics.
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1)A baton twirler throws a spinning baton directly upward. As it goes up and returns to the twirler's hand, the baton turns through 4.42 revolutions. Ignoring air resistance and assuming that the average angular speed of the baton is 1.95 rev/s, determine the height to which the center of the baton travels above the point of release.


2)A planet orbits a star, in a year of length 4.57 x 107 s, in a nearly circular orbit of radius 1.56 x 1011 m. With respect to the star, determine (a) the angular speed of the planet, (b) the tangential speed of the planet, and (c) the magnitude and direction of the planet's centripetal acceleration.

3)A rectangular plate is rotating with a constant angular speed about an axis that passes perpendicularly through one corner, as the drawing shows. The centripetal acceleration measured at corner A is n times as great as that measured at corner B. What is the ratio L1/L2 of the lengths of the sides of the rectangle when n = 1.66?

4)A star has a mass of 1.81 x 1030 kg and is moving in a circular orbit about the center of its galaxy. The radius of the orbit is 3.1 x 104 light-years (1 light-year = 9.5 x 1015 m), and the angular speed of the star is 2.5 x 10-15 rad/s. (a) Determine the tangential speed of the star. (b) What is the magnitude of the net force that acts on the star to keep it moving around the center of the galaxy?

All help is appreciated, thank you
 
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Hi jellis26, welcome to PF.
Go through the textbook. Collect the relevant equations to solve the problem.
show your attempts.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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