Blocks in a room which is being accelerated

Like Tony Stark

Homework Statement
The two bodies shown in the picture have the same mass and are inside a room which is accelerating to the right with $2 \frac{m}{s^2}$. The coefficient of static friction is the same for both bodies. Determine the minimum value of the coefficient of static friction such that the blocks don't slide with respect to the room and the tension.
Homework Equations
Newton's equations
I wrote the equations for $m_2$ with respect to the room, which are:
$x) T-Fr_1-f_1 *=0$
$y) N_1-P_1=0$

For $m_1$ we hace:
$x) N_2=f_2 *$
$y) T+Fr_2 -P_2=0$

Where $f*_1$ and $f*_2$ are the pseudo-forces and $Fr_1$ and $Fr_2$ are the friction forces that contain $\mu$

Then I solved for $\mu$ and got $\mu =0.6$

Are my ideas correct? Because I wasn't sure about the sign of the friction.

Attachments

• 70.2 KB Views: 16
Related Introductory Physics Homework Help News on Phys.org

mfb

Mentor
x is in vertical direction? An unconventional choice.
You could have shown the intermediate steps. I get a different answer.

Working purely in the single degree of freedom: m*g is a force towards "m2 goes down", m*a is a force against it (where a=2 m/s^(2)), m*g*μ is against it (friction from m1), m*a*μ is against it (friction from m2).
m(g-a) = mμ(g+a), μ = 8/12 = 2/3.

• Like Tony Stark

"Blocks in a room which is being accelerated"

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving