How Much Energy Is Lost to Friction When a Mass Pulls Down a Spool of Wire?

  • Thread starter Thread starter Sumbhajee
  • Start date Start date
  • Tags Tags
    Cylinder
Click For Summary
SUMMARY

The discussion focuses on calculating the energy lost to friction when a mass pulls down a spool of wire. The spool has an inner radius of 0.45 m, an outer radius of 0.60 m, and a moment of inertia of 0.91 kg*m². A mass of 1.35 kg falls a distance of 0.52 m, achieving a final speed of 79.900 cm/s. The key to solving this problem lies in applying the law of conservation of energy, accounting for gravitational potential energy, kinetic energy, and rotational energy of the spool.

PREREQUISITES
  • Understanding of gravitational potential energy (PE = mgh)
  • Knowledge of kinetic energy (KE = 0.5mv²)
  • Familiarity with rotational energy (RE = 0.5Iω²)
  • Concept of moment of inertia (I) in rotational dynamics
NEXT STEPS
  • Study the law of conservation of energy in rotational systems
  • Learn how to calculate moment of inertia for various shapes
  • Explore the relationship between linear and angular velocity
  • Investigate frictional forces in rotational motion
USEFUL FOR

This discussion is beneficial for physics students, particularly those studying rotational dynamics and energy conservation principles, as well as educators looking for practical examples of these concepts in action.

Sumbhajee
Messages
15
Reaction score
0

Homework Statement


A spool of thin wire (with inner radius r = 0.45 m, outer radius R = 0.60 m, and moment of inertia Icm = 0.91 kg*m2 pivots on a shaft. The wire is pulled down by a mass M = 1.35 kg. After falling a distance D = 0.52 m, starting from rest, the mass has a speed of v = 79.900 cm/s. Calculate the energy lost to friction during that time. http://schubert.tmcc.edu/res/msu/physicslib/msuphysicslib/20_Rot2_E_Trq_Accel/graphics/prob22_pulleyD.gif


Homework Equations





The Attempt at a Solution



I have been having a lot of trouble with these rotation problems and I am not sure where to start on this. Any assistance would be appreciated.
 
Last edited by a moderator:
Physics news on Phys.org
Consider the types of energy involved. You start with the gravitational PE of the mass, and as it falls you lose that and get KE plus the rotational energy of the spinning spool. Write out a law of conservation of energy for those.
 

Similar threads

Physics homework help needed -- A mass sliding down a ramp with friction
  • · Replies 14 ·
Replies
14
Views
3K
A spool of thin wire pivots on a shaft
  • · Replies 1 ·
Replies
1
Views
3K
Solving Part B: Acceleration of End B after String Cut
  • · Replies 1 ·
Replies
1
Views
4K
Finding M1 in a Mass Sliding Problem with an Angle and Friction
  • · Replies 4 ·
Replies
4
Views
2K
Rotating spool on table with friction
  • · Replies 12 ·
Replies
12
Views
5K
How Much Energy Is Lost to Friction in a Spool of Wire System?
  • · Replies 1 ·
Replies
1
Views
5K
Pulling on a cylinder and energy lost to friction
  • · Replies 1 ·
Replies
1
Views
4K
Maximum force pulling a wheel without it slipping
  • · Replies 2 ·
Replies
2
Views
2K
Energy Lost to Friction in Spool Experiment
  • · Replies 7 ·
Replies
7
Views
3K
Calculate CM Speed of Rod on Compressed Spring
  • · Replies 1 ·
Replies
1
Views
2K