Problem finding angular velocity

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SUMMARY

The problem involves calculating the angular velocity of a 9.65 lb uniform disk, which is pin-supported and subjected to a constant downward force of 1.45 lb. The radius of the disk is 0.470 ft, and the calculation is based on the relationship between torque, moment of inertia, and angular acceleration. The correct formula used is angular velocity final = angular velocity initial + angular acceleration multiplied by time. The user successfully resolved the issue after correcting numerical errors in their calculations.

PREREQUISITES
  • Understanding of torque and its relation to angular motion
  • Familiarity with moment of inertia for a uniform disk
  • Knowledge of angular kinematics equations
  • Basic principles of forces and acceleration in rotational dynamics
NEXT STEPS
  • Study the relationship between torque and angular acceleration in rotational dynamics
  • Learn about calculating moment of inertia for different shapes, specifically uniform disks
  • Explore angular kinematics equations in detail, including their applications
  • Investigate the impact of varying forces on rotational motion and angular velocity
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Students in physics or engineering disciplines, particularly those focusing on mechanics and dynamics, as well as educators seeking to clarify concepts related to rotational motion.

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[SOLVED] Problem finding angular velocity... !

Homework Statement




The 9.65 lb uniform disk is pin supported at its center and is acted upon by a constant force of P = 1.45 lb as shown. The system starts from rest. Radius of disk is .470 ft

The force P is going straight down from the disk and would spin the disk in a clockwise direction. The force P is at the end of a string.. making the disk spin.

Determine the angular velocity after 4.45 seconds. (rad/s, +CCW)

Homework Equations



I know this problem involves a constant accel equation. I believe the right one is angvelfinal = angvelinitial + a*t



The Attempt at a Solution



The issue i have is that i can't figure out how to relate the force acting on the disk to turn it into acceleration. I have tried setting "Force*Radius=(.5*Mass*radius^2)angaccel" and solving for angaccel and then multiplying it by the time in order to get my angvel but i am having no luck. Any help i appreciated.
 
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any other info i need to give guys?? i have been on this question for two days lol. I can finish it i just can't figure out how i get from a force in lbs pulling down on a string turning a disc... to the acceleration of the disc. I've looked through formulas and have had no luck anywhere.
 
thanks guys, i figured it out. I was doing it right but somehow my numbers were off somewhere.
 

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