Find Mass of Pulley in Atwood's Machine Homework

  • Thread starter Thread starter Tanahagae
  • Start date Start date
  • Tags Tags
    Machine
Click For Summary
SUMMARY

The discussion focuses on calculating the mass of a pulley in an Atwood's machine scenario involving two masses, m1 = 5.2 kg and m2 = 2.6 kg. The pulley is modeled as a uniform disk with a radius of 12 cm. Key equations include the conservation of energy and rotational kinetic energy, specifically K + (1/2)Iw² and Ei = mgh. The participant expresses uncertainty in applying the acceleration formulas and seeks clarification on the problem-solving approach.

PREREQUISITES
  • Understanding of Atwood's machine dynamics
  • Familiarity with conservation of energy principles
  • Knowledge of rotational kinetic energy concepts
  • Ability to apply kinematic equations
NEXT STEPS
  • Study the derivation of the conservation of energy in mechanical systems
  • Learn how to calculate rotational inertia for different shapes, specifically disks
  • Explore the application of kinematic equations in pulley systems
  • Investigate the relationship between linear and angular acceleration in rotational dynamics
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and dynamics, as well as educators looking for examples of problem-solving in Atwood's machine scenarios.

Tanahagae
Messages
8
Reaction score
0

Homework Statement


The two masses (m1 = 5.2 kg and m2 = 2.6 kg) in the Atwood's machine shown in The Figure are released from rest, with m1 at a height of 0.79 m above the floor. When m1 hits the ground its speed is 1.7 m/s.

Assuming that the pulley is a uniform disk with a radius of 12 cm, outline a strategy that allows you to find the mass of the pulley.

Determine the pulley's mass.

Homework Equations


Rotational Kinetic Energy: K + (1/2)Iw2
Conservation of Energy: Ki + Ui = Kf + Uf

The Attempt at a Solution


I am more or less stumped on this problem. Information that is known is that v0 = 1.7 m/s and vf = 0. The Ei = mgh (I think since the system starts at rest and m1 has Gravitation Potential Energy). Ef = (1/2)mv2 + (1/2)Iw2. All this is speculation since I am grasping at a way to solve this problem.

Also, from looking at other related problems people tend to find acceleration through the Kinematics v2 - v02/2(x - x0). However, I am not sure how to apply the acceleration of m1, all I know is that it translates through the pulley system.

Another possible acceleration I found was a = [(m1 - m2)/(m1 + m2)]g. This formula brought up a different acceleration than the previous, but once again I am not certain how to apply it.

Reassurance that I am on the right route, and a hint would be greatly appreciated.
 
Last edited:
Physics news on Phys.org
What is the question? Your problem is nothing but stated facts, and there is no question. Literally, not a single question mark.
 
Thank you for bringing that to my attention. I have spent so much time belaboring the issue through my mind that I completely forgot to actually spell out the question.

Although, no question marks does not mean there exist no questions.
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 102 ·
4
Replies
102
Views
8K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 17 ·
Replies
17
Views
3K
Replies
11
Views
1K
Replies
25
Views
4K
  • · Replies 15 ·
Replies
15
Views
7K
Replies
19
Views
2K
  • · Replies 97 ·
4
Replies
97
Views
17K
Replies
8
Views
10K