Engineering Newton’s Second Law of Motion — Collar sliding on a rotating rod

AI Thread Summary
The discussion focuses on the application of Newton's Second Law of Motion to a collar sliding on a rotating rod using polar coordinates. It emphasizes that the acceleration of the collar consists of radial and transverse components, but only the radial component is calculated when assessing the collar's acceleration relative to the rod. The transverse acceleration component is considered zero because the collar is constrained to the rod's motion. The rod exerts the necessary torque to maintain the collar's position. This understanding clarifies the dynamics involved in the collar's movement on the rotating rod.
mingyz0403
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Homework Statement
The horizontal rod OA rotates about a vertical shaft according to the relation dθ/dt=10t, where
dθ/dt and t are expressed in rad/s and seconds, respectively. A 250 g collar B is held by a cord with a breaking strength of 18 N. Neglecting friction, determine,immediately after the cord breaks, (a) the relative acceleration of the collar with respect to the rod, (b) the magnitude of the horizontal force exerted on the collar by the rod.
Relevant Equations
Newton's Second Law
The soultion used polar corrdinates. Acceleration in polar corrdinates have radial and transeverse components.When calculating the acceleration of collar respect to the rod, the solution only calculates the radial component of acceleration. Is it because the collar is on the rod, so the transeverse acceleration component of the collar is the same as the rod. Acceleration of collar respect to rod=Acceleration of collar-Acceleration of Rod. Therefore, the transeverse component of acceleration of collar respect to the rod is 0?
 

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mingyz0403 said:
Therefore, the transeverse component of acceleration of collar respect to the rod is 0?
Correct. The rod forces the collar with whatever torque is necessary.
 
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BvU said:
Correct. The rod forces the collar with whatever torque is necessary.
Ok, Thank you.
 
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