Pulley problem with moment of inertia

AI Thread Summary
The problem involves a 28.5 kg block (m1) on a horizontal surface connected to a 6.10 kg block (m2) via a massless string over a frictionless pulley with a moment of inertia of 0.140 kgm². A force of 231.3 N acts on m1 at an angle of 30.5°, and the goal is to determine the upward acceleration of m2. The initial approach of ignoring the moment of inertia was incorrect, as it is essential to apply both linear and rotational dynamics. Newton's second law for linear motion and the corresponding equations for rotational motion must be utilized to solve for the acceleration. Understanding the relationship between the forces acting on the blocks and the rotational dynamics of the pulley is crucial for finding the solution.
howsockgothap
Messages
59
Reaction score
0

Homework Statement


A 28.5 kg block (m1) is on a horizontal surface, connected to a 6.10 kg block (m2) by a massless string. The frictionless pulley has a s R = 0.087 m and a moment of inertia I=0.140 kgm2. A force F = 231.3 N acts on m1 at an angle theta = 30.5°. There is no friction between m1 and the surface. What is the upward acceleration of m2?

m2 is hanging off a pulley that's attached to the end of the surface as m1 is dragged across the surface by force F



Homework Equations



f=ma
I=?


The Attempt at a Solution



Initially I tried ignoring the moment of inertia and solving with just tensions but obviously that is not possible. My main problem is that (as you can see from part 2) I am not sure what equation I should be using in reference to the pulley's moment of inertia.
 
Physics news on Phys.org
howsockgothap said:

Homework Statement


A 28.5 kg block (m1) is on a horizontal surface, connected to a 6.10 kg block (m2) by a massless string. The frictionless pulley has a s R = 0.087 m and a moment of inertia I=0.140 kgm2. A force F = 231.3 N acts on m1 at an angle theta = 30.5°. There is no friction between m1 and the surface. What is the upward acceleration of m2?

m2 is hanging off a pulley that's attached to the end of the surface as m1 is dragged across the surface by force F



Homework Equations



f=ma
I=?


The Attempt at a Solution



Initially I tried ignoring the moment of inertia and solving with just tensions but obviously that is not possible. My main problem is that (as you can see from part 2) I am not sure what equation I should be using in reference to the pulley's moment of inertia.
You have correctly identified that you need to use Newton's second law for linear accelerations. What you now need to Newton's second low for Rotations - see: http://hyperphysics.phy-astr.gsu.edu/hbase/n2r.html
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...

Similar threads

Back
Top