Pulley Acceleration and Tension Relations

  • Thread starter Thread starter inv4lid
  • Start date Start date
  • Tags Tags
    Pulley
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
3 replies · 2K views
inv4lid
Messages
19
Reaction score
0

Homework Statement


Determine bodies' acceleration if their masses are the following: m1 = 25kg, m2 = 1kg, m3 = 3kg and the Tension of the ropes. Friction is neglected, as well as the mass of the pulley. It is considered that the ropes are perfect.

ta29Rnv7RYGxQ93HZbQQpg.png


m1 = 25kg;
m2=1kg;
m3=3kg;
___________
a=?
T1=?
T2=?
#

Homework Equations


For the first object we have:
T1-G1= m1*a; (the acceleration is oriented upwards)
a = (T1-G1)/m1;
For next ones, I guess:
The acceleration here goes downwards
T2-G2-G3 = -(m2+m3)*a;
a = (T2-G2 - G3) / -(m2 + m3)

Are the accelerations the same?
How would i find it?
 

Attachments

  • ta29Rnv7RYGxQ93HZbQQpg.png
    ta29Rnv7RYGxQ93HZbQQpg.png
    8.1 KB · Views: 452
Physics news on Phys.org
inv4lid said:
Are the accelerations the same?
What would happen if the accelerations were not the same?
You may safely assume that this is an ideal pulley, i.e. it changes the direction of the tension but not its magnitude. This will simplify your work.
 
kuruman said:
What would happen if the accelerations were not the same?
You may safely assume that this is an ideal pulley, i.e. it changes the direction of the tension but not its magnitude. This will simplify your work.
I need to get some numbers. How would i get the tension/acceleration? There is too much unknown data.
(i guess we can't get any of T)
 
inv4lid said:
I need to get some numbers. How would i get the tension/acceleration? There is too much unknown data.
(i guess we can't get any of T)
I think kuruman is trying to get you to relate ##T_{1}## to ##T_{2}##. If the pulley is ideal (frictionless and massless) what is the relation? Once you have the relation, you can solve the algebraic system.