Dynamics- Angular Impulse and Momentum Problem

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The problem involves a 30-kg reel mounted on a 20-kg cart, with a force of 50 N applied to a cable wrapped around the reel's hub. To find the cart's velocity and the reel's angular velocity after 4 seconds, the impulse-momentum equation is used, but the user struggles with relating the two variables, ω2 and v2. Key observations suggest that a constant torque is applied to the reel, leading to angular acceleration, while the total force on the cart and wheel assembly is determined by the applied force. The user is advised to ensure consistent dimensions in their impulse equation for accurate calculations. The discussion emphasizes the need for additional equations to solve for both velocities effectively.
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Homework Statement


The 30-kg reel is mounted on the 20-kg cart. If the cable wrapped around the inner hub of the reel, with radius 150mm, is subjected to a force of P=50 N, determine the velocity of the cart and the angular velocity of the reel when t=4 sec . The radius of gyration of the reel about its center of mass O is kO = 250 mm. Neglect the size of the small wheels.
Attached is a picture

Homework Equations


IG1+Σ \intMGdt=IG2


The Attempt at a Solution


I=mk2=1.875 kg/m2
So my impulse equation solves down to:
P*r*t=Iω2+mv2
I end up with 2 variables and 1 equation. What is my missing equation, or how do I relate ω2 and v2?
 

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Sorry no one has responded thus far.

Not my specialty, but I would base my computations on two interpretations:

1. Irrespective of the motion of the cart, there is a constant torque τ applied to the reel, with resulting angular acceleration, that torque being τ = P*r1 where r1 = radius of inner hub. Thus θ'' = τ/I and you have already computed I, hopefully correctly.

2. The only force applied to the cart + wheel assembly is P. So P = Mx'' for the assembly where M = total assembly mass (50kg).

If these observations hold then the problem is actually quite straightforward. I think they do. I notice that your "impulse equation" has inconsistent dimensions within it.
 

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