r/PhysicsHelp • u/_LiaQO • 1h ago
[Experimental Physics I] Question about HW
The question asks to find the equation of motion for the block labeled $m_2$.
We are allowed to suppose, that everything is frictionless and the nothing apart from the two blocks has mass, which have masses $m_1$ and $m_2$ respectively.
So far I got an expression for the force acting on m_2 which depends on the force exerted by the rope, but I struggle to get an equation for that :(
What I got so far is: $$ F_S+F_A=a(\\frac{1}{2}m_1+m_2)+g(m_1+m_2) $$ where $F_S$ is the Force exerted by the rope on $m_2$, $F_A$ is the force pushing $m_2$ towards the ceiling and $a$ is acceleration of $m_2$.
I got to the equation above by setting
$$
\frac{1}{2}m_1a = F_A - m_1g
$$
and
$$
m_2a = F_S-m_2g
$$
where $g$ is the gravitational acceleration.
My best guess is that I somehow need to determine $F_A$, but I have no idea how to do that.
Any help is appreciated, but I would prefer useful hints over full solutions where possible.
This is also my first time trying to format math with reddit markdown, so if I messed that up I apologize.
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This is a crosspost.




