What is Reaction forces: Definition and 64 Discussions
A rapid reaction force is a military or police unit designed to respond in very short time frames to emergencies. When used in reference to police forces such as SWAT teams, the time frame is minutes, while in military applications, such as with the use of paratroops or other commandos, the time frame is hours to days.
Rapid reaction forces are designed to intervene quickly as a spearhead to gain and hold ground in quickly unfolding combat or in rather low intensity conflicts, such as uprisings that necessitate the evacuation of foreign embassies. Because they are usually transported by air, such military units are usually lightly armed, but often extremely well trained to compensate for their limited to small arms and light crew-served weapons and the lack of vehicles, armor and heavy equipment like tanks.
Greetings, I have tried to find the reactions of the bearings on the Y direction in the intermediate shaft. but I couldn´t find the numerical results of the solutions
here is my attempt:
in order to find the forces I did the moment equilibruim around the point A and B
With FT1 FT2 and...
I have this question in my biomechanics class, and the way the teacher has solved it raised some questions with me.
This is the snippet of work from the lecture slides:
But, if we see the red variables acting as 'placeholders' for the value of respective forces, and the value of the force at...
So I am trying to understand how to estimate the amount of deflection [D] the vertical beam shown above would experience if the base it is attached to is accelerating at a constant acceleration [a] of 9.81 m/s.
I assume the Force [F] would be equal to weight of the vertical beam (mass x...
Summary:: The question requires us to determine the member forces using method of joints but I couldn’t figure out how to calculate the support reaction forces
I tried to use equilibrium equations to solve the question but the force applied will be canceled out, and eventually the reaction...
Given: r1 = 0.75 r2 = 1.5
Ok, i have done statics and dynamics, but this book does things differently than the way i accomplished it in the previous classes. This is for mechanical engineering design class.
Here is my question. They take sum of the moments along X, which goes through the center...
I know that
##\vec{v_c}=(\omega_1;-\omega_2;0)×(L;-r;0)=0##
So ##\omega_2=\frac{r\omega_1}{L}##
Then, using the system of coordinates shown in the picture and ##\Sigma M_z## I can find the reaction force in ##C##.
But how can I find the reaction forces on ##A## and ##O##? I mean, what system...
If you do the sum of vertical forces and sum of moments, you're always left with an unknown.
Vertical Forces: Ray + Rby + Rcy = 59kN + 45kN (1)
Sum of Moments about A: (59 x 1.85) - (Rby x 3.7) - (Rcy x 4.8) + (45 x 6.5) = 0...
Hi everyone, I'm new here so I hope I'm posting this in the right place.
I'm struggling to duplicate the horizontal reaction forces being generated in an L shaped beam. Typically I like to do hand calculations and verify my answer using Solidworks, but in this case I can't seem to wrap my head...
Hello new to the forum.
I'm a builder by trade and enjoy studying the concepts behind the things I build.
My problem is:
A typical concrete post and base panel with a wooden fence. Unit mass approximately 350kgs including the foundation concrete around the posts.
2.0m wide x 2.0m above...
Homework Statement
Homework Equations
Using dimensional plane in the vertical y and horizontal x.
##\Sigma##Fx = 0
##\Sigma##Fy = 0
##\Sigma##Mz = 0
The Attempt at a Solution
I have detached the 2 members at B and analyze them both separately. The 14 kip force is throwing me off though...
Homework Statement
Consider beam “A-B” and strut “C-D” from Figure QA1. The beam “A-B” is hinged at point “A” and hinged with strut “C-D” at point “C”. It has an applied force of 8 kN applied at point B as shown in Figure QA1. Strut “C-D” is hinged at point “D” and it is also hinged with beam...
Homework Statement
The problem asks to find the reaction forces for each of the bearings. For such bearings, the reaction forces can be looked up in a textbook, but they just act perpendicular to the shaft.
Homework Equations
Sum of the forces and moments = 0.
The Attempt at a Solution
I...
I am having trouble recognizing reaction forces. for example, problem 6.8 on pin C there is no y component, the argument there was because there is no vertical member attached to C. That is understandable, but if we follow the same logic then there should not be an x component on pin A in...
Homework Statement
Two cylinders, each with a mass of 10kg, are lying on an L profile.
Neglect the thickness and weight of the L profile.
Calculate the reaction force in b and e.
Homework Equations
G = mg
The Attempt at a Solution
So I tried to make a free body diagram of the cylinders.
I...
Homework Statement
I'm having a hard time finding the reactions at the supports and the force exerted by the spring.
Given:
20 lbs
25 lbs
35 lbs
k = 200 lb/ft
lo = 2.5 ft
members are 4 ft longHomework Equations
ΣM
∑Fy = 0
∑Fx = 0
The Attempt at a Solution
I tried solving for the reactions...
Homework Statement
Determine all member forces and state if they are in tension or compression, in particular I am looking for member AE and AB[/B]
Homework EquationsThe Attempt at a Solution
Ok so we are supposed to redo the problems from our exam, only I can't figure out how to find the...
I have been reading many examples of control volume calculations regarding nozzles
They all end up with a reaction force on the nozzle in the direction of the flow.
I can't understand this from a Conservation of momentum perspective.
I would expect that the reaction force, by Newtons third...
Homework Statement
Calculate reaction forces for truss. Truss is attached in picture.
Homework Equations
ΣFx=o
ΣFy=0
ΣM about reaction point=0
The Attempt at a Solution
attached in picture
I find the common physics problem of accelerating boxes that are touching very confusing. (To be clear, boxes are on surface, force comes from one side and all boxes accelerate. Questions typically ask about magnitude of force between particular boxes).
Once the boxes are accelerating, why is...
Homework Statement
Homework Equations
∑Fx=0
∑Fy=0
∑M=0
The Attempt at a Solution
[/B]
I am just concerned with part a.
I got the correct answers doing this:
First, FBD of segment AB:
+cw ∑M_A=0: -136 - 6*By = 0
By = -22.7N
two ways to get Ay:
one:
+cw ∑M_B=0: -136 + 6*Ay = 0
Ay =...
Homework Statement
Determine the components of the forces acting on each member of the pin-connected frame shown.
(the frame shown is drawn as a free-body diagram in the image provided below (the top-most portion) and is correct)
Homework Equations
Equilibrium equations:
∑M=0
∑Fx=0
∑Fy=0
The...
This is the question: http://i.imgur.com/Ex2Yx4l.png
I have calculated all the angles in the frame, and have drawn line of forces so that the reaction force at x, reaction force at y, and the 10KN meet up. From then I am stuck, and don't know how to find the angle theta...
Hello all,
I am in the process of calculating reaction forces on an object, and need some help.
Attached is a free body diagram of an object in two different views- one looking from the sides (z-x plane) and one looking it in birds eye view. (xy plane)
7 variables I am looking to solve are...
Homework Statement
I am given the forces on picture and I´m asked to find the reactions on both supports. I see they are pin supports so they ask me for 4 unknowns.
Homework Equations
Sum of forces in both directions equal to zero
Sum of torques wrt a convenient point equal to zero
THREE...
Homework Statement
The right angle boom which supports the 230-kg cylinder is supported by three cables and a ball-and-socket joint at O attached to the vertical x-y surface. Determine the reactions at O and the cable tensions.
Homework Equations
M [/B]= r x F
unit vector =...
Homework Statement
For my statics homework, we are directed to:
Draw the free body diagram and use the force and moment equilibrium to determine the support reactions for the following systems
I'm having a bunch of trouble with problem 4.10, which is displayed in the following picture
I'm...
Hello,
I am analysing a 3D D shaped Incompressible Neo hookean material in contact with a semi cylinder using Ansys 14.5 APDL. The input values provided are C10=2737674.313898 and mass of D shape geometry to be 8 kg/m. I have converted these values into density and Shear Modulus as required in...
Hello, so I've been given this question and I get a different anwser then my friends. Can you check if what I wrote is right? If its wrong then can you tell me what have I done wrong? Sorry for the quality of the picture but my Paint skills are not so great :)
I was measuring to the right...
[b]1. Hi, The problem:
A roof support frame has various leadings on it. The frictionless pin joint at points A has vertical and horizontal reaction forces. The rollers at point B allow free movement in the horizontal direction and has a vertical reaction.
a/Calculate The total Horizontal...
Homework Statement
The shaft carries two particles of mass m, and rotates about the z-axis with the constant angular velocity ##\omega##. Determine the x- and y-component of the bearing due to imbalance.
The Attempt at a Solution
Rotation only around the ##z-##axis so ##\omega _{x}=\omega...
Homework Statement
Rod AB is attached to a collar at A and rests against a roller at C.
a = 107mm,
l = 642mm,
P = 110kN and
Q = 30kN, determine:
The reaction at A (by the vertical rod) (Unit: kN)
The magnitude of the reaction at C (Unit: kN)
Homework Equations
This is my first...
Homework Statement
A bowling ball is suspended from a ceiling hook using a thin piece of rope. If the rope is
exerting a 65 N force upward on the ball, describe the corresponding reaction force in
terms of:
(a) its magnitude
(b) its direction
(c) on what object it is exerted
(d)...
My problem here seems that I can't figure out how to solve for my unknowns. I have 3 equations for force, and I'm not sure if that equation I have for the moment around the origin counts as 3 new independent equations if I split them up into i, j, and k components. If that is allowed, then I...
Homework Statement
Problem 4.36
http://xps2pdf.co.uk/4c82ad8dcb91d5507169e0a18804ea30bf81d592/4.36.pdf
Homework Equations
The Attempt at a Solution
I am not sure if I am doing this correctly..there is a lot of information that I am not using to solve the problem (i.e. all the different...
I am looking to find the reaction forces on the bottom of the rectangular shape I have included (sorry for the crude diagram). I have a moment on the top right beam (390600 lb/in) and a distributed load of 160 lb/in across the entire surface of the top of the rectangular prism. I am looking...
Homework Statement
I´ll show it with a picture:
Homework Equations
Static equilibrium, Sum Forces=0 ; Sum Moments= 0
The Attempt at a Solution
With the Fx, and Fy equations I can calculate the reactions Rx and Ry but I don´t understand the moments equation:
Sum M around...
How do I find reaction for loading condition shown in image. I have no idea how to tackle this type of problem. Please help.
http://img6.imageshack.us/img6/725/partilaudl.jpg
Uploaded with ImageShack.us
Homework Statement
Homework Equations
r * \alpha = atan
r * \omega^2 = arad
The Attempt at a Solution
arad = (L/2)(3g/L) = 3g/2
atan = (L/2)(3g/2L) = 3g/4
This is not a question from a textbook, I am just supposing a situation.
A book is lying on a table with some friction. If I push on the book, the book will push on me with an equal and opposite force; the book will then push on the table with friction, and, in return it, the table will push...
hello forum,
consider an object attached to a rope and rotating in a horizontal loop. The tension T in the rope provides the centripetal force points toward the center of the loop.
But forces always exist in pair (action-reaction).
what is the other force in the pair where one of the...
Homework Statement
http://img101.imageshack.us/img101/9546/3dstats.jpg
Pole AB is supported at point A by a pin joint, and held at point B by two wires, BC and BD, as described in the drawing. At point B acts on the pole force F which equals 500 [N]. The force F acts on a horizontal...
Homework Statement
Homework Equations
The Attempt at a Solution
The problem I'm having is that I'm not sure how to work out the reaction forces because of the applied moment of 50kN.m. I know that the formulas are the sum of forces in a single direction equals 0 and the sum of...
I have a 2 questions regarding Newton’s third law and I will explain them using examples:
1. Body A is pushing against Body B with a force F(AB), Now body B will push against body A with a reaction force F(BA) equal but opposite to F(AB). Now shouldn’t be another reaction force F2(AB) due to...
Hello,
Can the reaction forces at the mounting (fixed) holes of a component in a static structural analysis be used directly to find out the forces acting on the mounting bolts?
If my understanding is correct, the force in the direction in the axis of the bolt will be used to find the...