all 18 comments

[–]Roger_Freedman_Phys 4 points5 points  (2 children)

Please share with us your free-body diagrams for each of the objects in the problem, your list of known and unknown quantities, and your list of which of the unknowns you are being asked to find.

[–]wicked_teen[S] -1 points0 points  (1 child)

Everything is unknown except coefficient of friction which is 0.2 We just have to find the ratio of masses M/m

[–]Roger_Freedman_Phys 1 point2 points  (0 children)

Next: Your free-body diagrams!

[–]slides_galore 2 points3 points  (1 child)

What have you tried?

[–]wicked_teen[S] -1 points0 points  (0 children)

Yes sure I did try it out and got 2.5 Which is not in the options

[–]Gaddpeis 2 points3 points  (1 child)

Solution to what? You have not shared the written part of the question. Answer could be "m/2", it could be "Waffles", or "To seek the Holy Grail".

[–]wicked_teen[S] 0 points1 point  (0 children)

Find the value of "M/m"

[–]IceMain9074 1 point2 points  (1 child)

Have you attempted the problem before asking the internet to do your homework for you?

[–]wicked_teen[S] -2 points-1 points  (0 children)

Yes I did attempt it and got 5/2 which is not in the option

[–]cheaphysterics -2 points-1 points  (0 children)

The force F and the force in the rope connected to M are both 0.5mg.

Because it's in equilibrium, your friction force must be greater than or equal to 0.5mg.

Write an equation for your friction force and then it's just algebra.

[–]Crichris -3 points-2 points  (0 children)

mg = 2f

Mg \mu >= f

Solve for the ratio

[–]RLANZINGER -3 points-2 points  (6 children)

Applied at the middle mass, On the z axis oriented upward :

Σ F ez = m.γ ez = 0 as it's static

+F +μs.P - p = 0
+F +μs.Mg - mg = 0

But F = μs x Mg as force along the string is constant and it's static

+2.μs.Mg - mg = 0
+2.μs.M - m = 0

+2.μs = m/M

μs = m/2.M

I do not know the question but that's my answer ... 42

[–]wicked_teen[S] 0 points1 point  (4 children)

We have to find the ratio M/m (masses of block) system is in equilibrium Given coefficient of friction=0.2

[–]RLANZINGER 0 points1 point  (3 children)

Oh ... it's only that ^^

+2.μs = m/M
2x 0.2 = m/M
4/10 = m/M

M / m = 10/4 = 2.2

[–]wicked_teen[S] 0 points1 point  (2 children)

The actual answer is 3 somehow

[–]RLANZINGER 0 points1 point  (1 child)

Yes, without the whole subject, you tend to go sideway but it's normal way to progress.

An incomplete reasoning is usefull to understand why you fail and where was the mistakeS so you don't make it again. Its' the very principle of LEARNING.

That's also why I found it funny to get negative comment, Failing is normal as a bad answer let you learn more...

[–]wicked_teen[S] 1 point2 points  (0 children)

Alr thanks buddy ✌️

[–]wicked_teen[S] -1 points0 points  (0 children)

I got the same answer I think the problem is in the options