Pulley system -- Calculate the mass that balances this pulley system

AI Thread Summary
The discussion focuses on calculating the mass that balances a pulley system, with an emphasis on understanding the free body diagram. The user has calculated the force exerted by mass A but struggles with the tension in the rope and its variation. Clarification is sought on the tension forces acting on both masses A and B. Participants suggest working symbolically throughout the calculations to simplify the process and avoid unnecessary arithmetic. The conversation highlights the importance of accurately representing forces in a free body diagram for solving pulley problems.
FFTB
Messages
1
Reaction score
0
Homework Statement
Calculate the mass of mB that makes the system to be in equilibrium. Neglect the possible friction
Relevant Equations
Sin cos tan
pulley.png

I've been stuck at this pulley system for a while.
I've calculated the force of which A pulls => FA = sin25*50*9.82 = 208.5 N
But I get stuck on the free body diagram.
Can someone help and explain the freebody diagram
uträkning.png
 

Attachments

  • pulley.png
    pulley.png
    4.3 KB · Views: 149
Physics news on Phys.org
Let T be the tension in the rope. Does it vary along the rope? What is the tension force on mass A? On mass B?
 
Your work looks ok except for ##m_B=T##. What have you missed out?
As a matter of style, learn to work entirely symbolically, only plugging in numbers at the end. It has many advantages.
In the present case, you could have avoided some arithmetic since g would cancel.
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Thread 'Electric field due to charges between 2 parallel infinite planes'

TL;DR Summary: Find Electric field due to charges between 2 parallel infinite planes using Gauss law at any point Here's the diagram. We have a uniform p (rho) density of charges between 2 infinite planes in the cartesian coordinates system. I used a cube of thickness a that spans from z=-a/2 to z=a/2 as a Gaussian surface, each side of the cube has area A. I know that the field depends only on z since there is translational invariance in x and y directions because the planes are...
View full post »

Similar threads

Pulley system problem: 6 Pulleys and 1 Mass
Replies
5
Views
913
System of two pulleys and three masses
Replies
22
Views
6K
Experimental Design: Pulley and Mass Hangers
Replies
30
Views
3K
Force applied on the pulley of a system
Replies
8
Views
3K
Explain friction in a pulley system
Replies
13
Views
7K
Calc Forces on Pulleys: 200N, 300N Masses, No Friction
Replies
1
Views
2K
Acceleration of a mass lowered by a motor (Help with Non-Ideal Pulley)
Replies
4
Views
2K
Motion of a system that has two masses and three pulleys
Replies
11
Views
2K
Time period of SHM & Energy conservation in pulley-spring-block system
Replies
24
Views
3K
Pulley system, find the acceleration and tension
Replies
40
Views
5K

Hot Threads

Recent Insights

Back
Top