In classical mechanics, a particle is in mechanical equilibrium if the net force on that particle is zero. By extension, a physical system made up of many parts is in mechanical equilibrium if the net force on each of its individual parts is zero.In addition to defining mechanical equilibrium in terms of force, there are many alternative definitions for mechanical equilibrium which are all mathematically equivalent. In terms of momentum, a system is in equilibrium if the momentum of its parts is all constant. In terms of velocity, the system is in equilibrium if velocity is constant. In a rotational mechanical equilibrium the angular momentum of the object is conserved and the net torque is zero. More generally in conservative systems, equilibrium is established at a point in configuration space where the gradient of the potential energy with respect to the generalized coordinates is zero.
If a particle in equilibrium has zero velocity, that particle is in static equilibrium. Since all particles in equilibrium have constant velocity, it is always possible to find an inertial reference frame in which the particle is stationary with respect to the frame.
Please help me to understand why it is wrong to take moment for point ## A’ ## , because I think static equilibrium should be static equilibrium for any point in space.
Method 1：
$$ \sum{M_A=0:} $$
$$ F\cdot R=\left( F_p \right) _x\cdot \left( R-y_p \right) +\left( F_p \right) _y\left( x_p...
Attempted creating equations for zeros of torque and components of forces in x and y as seen in picture. Got lost with having only variables and the d & 2L for the length of the beam. Not sure how to do the question with two points of contact between the beam and the sign. Is the center center...
My approach to this problem is to recognize that the tetrahedron being still means that net torque is zero and net force is zero.
Fd is given
Fa + Fb + Fc = -Fd
Fa X a + Fb X b + Fc X c = <0,0,0>
This can be split up into a series of 6 equations, 2 for each component.
However, this is where I...
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I' m trying to make a linear static analysis (Finite Element Analysis) on the following hand tool. I want to determine the boundary conditions. In order to do that I have decided to use a force couple to represent the forces that a bolt exerts on the jaws of this spanner.
Despite using...
In the experiment, a cart on an inclined plane of 30 degrees is hooked with the force metre by a line. The line is tension T. It is also subjected to the force of gravity Fg. This makes the cart in static equilibrium. But since the cart is hooked with a line, it does not slide down. The net...
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Material: most laptop stands are made with 6mm acrylic thickness, hence this is what I will use. Also I already have this material at home.
I am...
A diagram of the physical situation is below:
Choosing the positive ##y## direction to be upwards and the positive direction of rotation to be counterclockwise, Newton's linear second law gives:
$$-m_D g + F_L + F_R = 0$$
where ##F_L## is the magnitude of the force exerted on the bar by the...
I am not sure which other forces I should consider besides those 3. I cannot consider tensions due to the massless rod on the masses since those will not add up to zero.
If I can determine the weight of that heavy object placed on the plank, I will be able to determine the stretch of that wire. But, when using the second condition for static equilibrium (torques of the system equal to 0), I always end up with two unknowns, no matter what point of rotation I...
i really can't understand the answer of this question, is the question 1.3 in fluid mechanics by Frank ,M White
For the triangular element in Fig P1.3, show that a tilted free liquid surface, in contact with an atmosphere at pressure pa, must undergo shear stress and hence begin to flow.
i...
I know I have to find the x and y components of T1 using 400cos(55) and 400sin(55) and I know that the x-component of T1 will = the x-component of T2 but opposite sign to give 0. But idk how to get there and what do to for the y-component. I think I found the weight, I think it’s 32.42g but I’m...
Homework Statement
https://imgur.com/v13K6sE
a uniform rod of mass m is placed as shown, with one of its end resting on a smooth wall while 1/4 of the rod's length is sticking out of a rough table. Find the net force the table exert on the rod at the corner.
Homework Equations
i drew the free...
Homework Statement
A block of uniform density experiences a force F to the right, applied 5/3 m from the bottom of the block. The block is 2 m high and 1 m wide. Take the pivot point to be the point at the bottom right of the block. Find the value of the force that is just able to tip the box...
Hi,
I'm not used to communicate physics in English, so my language may be a bit off.
This task is fairly simplistic. It's a figure which is held up in points A and B (both having an x and y force exerted on them), and the figure has a joint C. It is depicted in attached files.
The answers...
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Long time reader, first time poster..
I hope someone out there can help me. I'm designing an add-on to an existing piece of equipment and I'm unsure of how to calculate the resultant force output from a hydraulic cylinder.
On a straight push, the chosen hydraulic cylinder has an...
Homework Statement
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Homework Equations
∑F=0
The Attempt at a Solution
So in my eyes, you...
Homework Statement
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A) What is the tension in the string at 0 cm
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Homework Statement
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Homework Equations
ΣF=0
Ffr=μFN
F=ma
The Attempt at a Solution
I...
What I've attempted to do is resolve vertically and horizontally:
T1sin(30)+T2sinΘ+T2=9g
T2cosΘ=T1cos30
After that... I'm completely stuck. Any help would be appreciated, I've spent so long on this I bet I'm just missing one simple thing.
Thanks in advance
Homework Statement
Consider a rigid 2.60-m-long beam (see figure) that is supported by a fixed 1.30-m-high post through its center and pivots on a frictionless bearing at its center atop the vertical 1.30-m-high post. One end of the beam is connected to the floor by a spring that has a force...
Homework Statement
Two linear springs with stiffness Kh, Kv are attached to a single mass m at right angle to each other, i.e; one of the spring(Kh) is in the horizontal direction(x-axis) and the other(Kv) is in the vertical direction(y-axis).
A constant force F is being applied to the mass...
ANKIT SAJWAN
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free body diagram
mass
mechanic
springs
staticequilibrium
Homework Statement
Hi There,
I'm having trouble understanding (what I guess should be) a simple concept and so I can't apply it to a project I'm working on (also kind of rusty on torques and mechanics problems)
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Homework Statement
A bridge, constructed of 11 beams of equal length L and negligible mass, supports an object of mass M as shown in the picture.
Assuming that the bridge segments are free to pivot at each intersection point, what is the tension T in the horizontal segment directly above the...
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1. Homework Statement
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Homework Statement
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Homework Equations
Not allowed...
If you were to look at a simple 2D or 3D static equilibrium diagram, where a mass is suspended by multiple ropes at different angles, my gut feeling is that there is a fairly simple proportion between the distance between the center of mass and the rope (the distance created opposite of the...
Homework Statement
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Homework Equations
F_NET = 0
T_NET =0
The Attempt at a Solution
I thought both A and B were...
Homework Statement
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Homework Statement
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Homework Statement
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Hello! I just need someone to check my work here. I already turned in the homework with my hunch, but now I just want to check my work because it is killing me not knowing 100% :) I am having strong conflicting thoughts on particular parts and thought I'd post it here for clarification. I will...
Homework Statement
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Homework Equations
Virtual work, but...
I drew a FBD about point A and came up with the two equations:
∑Fx=0 20sinθ - T-ab(cos70)=0
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My answer is not coming out so I either messed up on the FBD or the equations, some help would be appreciated. I'm on 3-10 by the way.
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1. Problem statement
In figure, what magnitude of (constant) force F applied horizontally at the axle of the wheel is necessary to raise the wheel over an obstacle of height h=3.00cm ? The wheel's radius is r=6.00cm , and it's mass is m=0.800 kg.
Homework Equations
Balance of forces: Fnet=0...
Figure:
1. Homework Statement
We know system is in equilibrium and we are given the mass m, and the distances d, r1, and r2.
We assume that the rotational inertia of the bar is negligible.
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Homework Equations
Torque = radius × Force
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Homework Statement
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Homework Equations
F=ma
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The Attempt at...
Q: Why does the pin have a vertical force in this diagram (Static equilibrium)?
The diagram depicts as follows:
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Homework Statement
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In a recent class, my instructor covered the Kinetic Theory of gases. My question is in regard to the theory which states
1) The size of the individual molecues in a gas are so small that their volumes can be considered negligible.
The instructor then mentioned that the paticles in the gas can...
Homework Statement
Homework Equations
Static equilibrium: Net force & net torque = 0
The Attempt at a Solution
Am i doing this correctly for part a? [/B]