Homework Statement
What weight WB will cause the system to be in equilibrium? Neglect all friction, and state any other assumptions.
Homework Equations
ΣF=0
The Attempt at a Solution
I can't figure out what I am doing wrong with these pully problems, I tried putting in resultant forces at...
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.
What are the forces at points a and b?
Homework Equations
Torque = radius × Force
Force = mass *...
Homework Statement
Here's a screen shot of the problem statement:
http://i.imgur.com/IRI02Ne.png
For the purpose of this post, I'll label the given information as:
a = left side of ladder (2.5m)
a' = distance from floor to the point where the man is standing (2.0m)
b = right side of ladder...
Homework Statement
A man stands on a board of negligible mass with a length of 10m is supported by 2 cables, one on the left on one on the right, with a tension of 300N and 200N respectively. How much does the man weigh in Newtons?Homework Equations
F=ma
Torque= F*lever arm
The Attempt at a...
1) Problem:
An individual holds a ball of mass 3 kg in his hand in static equilibrium. The biceps brachii attaches a distance of 2 cm from the centre of rotation of the elbow joint, and the muscle's line of action is directed at an angle of 115° counter clockwise from the forearm. The forearm...
Q: Why does the pin have a vertical force in this diagram (Static equilibrium)?
The diagram depicts as follows:
A mass (M) sits a a distance (d) away from the end of a board of length L. The board has a mass of m and is held to a wall by a pin and string. The string has a tension (T) and is at...
We're given a problem: A 2.0 kg mass hangs from a rope attached to an unknown mass m on a frictionless ramp inclined at 20 degrees above the horizontal. This is drawn as a diagram which shows the incline at 20 degrees where the hanging mass is 2.0 kg and the attatched mass on the frictionless...
Homework Statement
For what m1 will the illustrated pulley system be in static equilibrium if m2 = 60 kg?
Homework EquationsThe Attempt at a Solution
im supposed to use the change in lengths but don't know how to do it
Homework Statement
See the attached sheet, I had missed todays class due to dentist and I found out we had an assignment due today by end of day, I am having trouble learning this on my own, I am trying right now. Could anyone help me with the solutions?
Homework Equations
Question one is...
Homework Statement A Ladder weighs 20 Lbs. IT rests against a smooth wall at point B. Theta=45. If you pull the ladder at its midpoint, how much force is needed to make it slide at point A? u=.6.
The ladder is 15 ft long, Point b is the top and point A is the bottom. 45 Deg is the bottom angle...
Homework Statement
A horizontal scaffold, of length 2.00 m and uniform mass 50.0 kg, is suspended from a building by two cables. The scaffold has dozens of paint cans stacked on it at various points. The total mass of the paint cans is 80.0 kg. The tension in the cable at the right is 830 N...
Homework Statement
I have a question about the following question:
Firstly, shouldn't there be a normal force for each hand (part a), but here they treat it as one normal force.
Also in part b, why isn't the torque for Fn1h = 0? Since that is the pivot point, isn't the moment arm zero?
Homework Statement
This isn't exactly a HW question, it's a question in my statics midterm today, he wants the reactions at the supports B and C, which is easy but the problem is this 60 N.m moment, all my friends were like :" let's just sum the moments around B ( due to the 50 N and the...
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]
Homework Statement
The answer is to be given in terms of L and w. The picture shows a beam of weight w and various blocks on it also each of weight w. It also shows the gravitational force acting downward on the center of gravity of the beam. The beam rests on a triangular pivot point.
2...
Homework Statement
You are designing the crosspiece for the A-frame structure in the figure below. Beams AB and AC are 3.35 m long and have a mass of 350.0 kg each. How much tension must the crosspiece EF withstand? Assume that the mass of the crosspiece and the friction at points B and C are...
Homework Statement
A rope of negligible mass is stretched horizontally between two supports. When an object of weight 3160N is hung at the centre of the rope, the rope is observed to sag by 35.0cm. What is the tension in the rope?
Homework EquationsThe Attempt at a Solution
[/B]
Sum of...
Let us imagine that there is a Massless spring with fixed at one end.
Unloaded length = L
Spring constant: = k
Mass = 0The spring is at static Equilibrium
Force: F
Displacement: d
F = k d,
elongated length: L+d
If I remove F, what will happen ?
1. Spring return to...
Homework Statement
The system shown in Fig. 2-6 is in static equilibrium. Use the principle of virtual work to find the weights A and B. Neglect the weight of the strings and the friction in the pulleys.
Homework Equations
Conservation of gravitational potential energy.
The Attempt at a...
A uniform vertical beam of mass 40 kg is acted on by a horizontal force of 520 N at its top and is held, in the vertical position, by a cable as shown.
a) Draw a free-body diagram for the beam, clearly labeling all of the forces acting on it.
b)Calculate the tension in the cable...
Homework Statement
A 30Kg neon sign is suspended by two cables, as shown. Three neighbourhood cats (5.0 Kg each) find the sign a comfortable place. Calculate the tension in each cable with the cats are in the positions shown.
Homework Equations
xCM = m1x1 + m2x2 ...
Homework Statement
A uniform vertical beam of mass 40kg is acted on by a horizontal force of 520N at its top and is held, in the vertical position, by a cable as shown in the attached picture.
a) Calculate the tension in the cable
b) Determine the reaction forces acting on the beam by the...
Homework Statement
A diving board 3.00m long is held down at the left end and is supported underneath at a point 1.00m to the right of the hold. A diver weighing 500N stands at the other end. The diving board is of uniform cross section and weighs 280N. Find (a) the force at the support...
Homework Statement
Two supports, made of the same material and initially of equal length, are 2.0m apart. A stiff
board with a length of 4.0m and a mass of 10 kg is placed on the supports, with one support
at the left end and the other at the midpoint. A block is placed on the board a...
Unfortunately there's no link to the test. This is from the test administered a month ago.
Homework Statement
A choppah is flying horizontally at constant speed. A perfectly flexible uniform cable is suspended beneath the choppah; air friction on the cable is NOT negligible.
Which of...
a man is trying to fix the light bulb at the top of his house ceiling.to reach the bulb,he is using a stepladder that is in equilibrium state.sides AC and CE are each 9.0 m long and hinged at C.Bar BD is attached with a rod that is 3.0 m long,halfway up.The man who is climbing 5.0 m along the...
Homework Statement
Two solid steel shafts are coupled together using meshed gears. Determine the angle of twist of end A. Shaft DC is fixed at D.
Homework Equations
angle of twist = torque * shaft length / ( polar moment of inertia * shear modulus)
balance of forces where the two gears...
Homework Statement
uk of fraction between bar and both surfaces is 0.2. Bar weighs 5 kg.
i) Is the bar in static equilibrium? If not, which end will fall down and which end will go up?
Homework Equations
F-uk*FnThe Attempt at a Solution
Not sure how to even begin analyzing this. I cannot...
Homework Statement
Homework Equations
How to do this question ??
The Attempt at a Solution
I know sum of torque and force = 0
at fapplied i got torque = 25sin(45) * 3.8m = 67.18N ..
But don't know what to do next !
Homework Statement
Suppose we take a 1 m long uniform bar and support it at the 22 cm mark. Hanging a 0.29 kg mass on the short end of the beam results in the system being in balance. Find the mass of the beam.
Homework Equations
\tau=F*r
The Attempt at a Solution
I set it up so that...
I have a problem.
Lets say there were two pulleys put at equal height.
You have a metal ring and attach three wires to it.
At the end of each wire, have three weights of mass w.
One weight hangs down, one weight goes over one pulley and the other over the other pulley.
The system goes to...
So with this problem, I have been thinking about it. Since it is in equilibrium, I know the sum of forces and torques will be equal to zero. However, I'm not sure how the height, h, fits into this. I know the weights have a force and are a distance away from that fulcrum, d and 2d, so I could...
Virtual work principle states: δW = \sum^{N}_{i=1}\vec{F}_{i}\centerdot δ\vec{r}_{i}
And from this, we can see that if a system is to be in equilibrium we have
δW = (\sum^{N}_{i=1}\vec{F}_{1} \centerdot \frac{\partial \vec{r}_{1}}{\partial q_{1}})δq_{1} + \cdots = 0
Where did q come...
Homework Statement
A diving board of length L is supported at a point a distance x from the end, and a diver weighing w1 stands at the free end (Figure 1) . The diving board is of uniform cross section and weighs w2.
(Figure 1)
Find the force at the support point.
Find the force at the end...
1. What occurs during static equilibrium?
3. The net force and net torque on the object is zero. The acceleration of the object is zero too. Would velocity of the object also be zero? Or no because it has constant velocity?
Homework Statement
Homework Equations
Ʃτ = 0
τ = rFsinθ
The Attempt at a Solution
I'm not even really sure where to start with this. My first thought was that it's not moving, so presumably the forces sum to 0. I also thought of treating the point where the net is exerting...
Homework Statement
A horizontal beam of weight W is supported by a hinge and cable as shown. The force exerted
on the beam by the hinge has a vertical component that must be:
Answer is nonzero and up.
The pull P is just sufficient to keep the 14-N block and the weightless pulleys in...
Homework Statement
what magnitude of force applied horizontally at the axle of the wheel is necessary to wheel over an obstacle of height h = 0.108 m? The wheel's radius is r = 0.698 m and its mass is m = 1.71 kg.
Homework Equations
I know that in order to have a static equilibrium we...
Homework Statement
A uniform strut of length, L and weight 780 N is free to pivot about point P where it is attached to the wall (see diagram) A weight W = 815 N hangs straight down from the end of the strut. A rope is attached to the same end as the load and the wall completes the support as...
Homework Statement
A block of weight 50N is hung by 3 cables from the ceiling. Each rope ZA, ZB, ZC converges at Z so that they form a tetrahedron. (ZA=ZB=ZC=AB=BC=CA). Find the magnitude of the tension of each cable.
a=0
tetrahedron symmetryHomework Equations
F=mgThe Attempt at a Solution
I...
Homework Statement
See:
http://www.aapt.org/physicsteam/2010/upload/2010_FmaSolutions.pdf
Question 11Homework Equations
T_net = 0
F_net = 0
The Attempt at a Solution
Start with F_net = 0:
Let T1 be the force of tension on the left, T2 on the right
T1cosθ=T2cosθ
Y components:
T1sinθ+T2sinθ = mg...
Homework Statement
I attached the original problem and a diagram I made with the variables on it. Basically we have a rod hanging from a wire at an angle theta with tension and the other end floating in water. So there is T=tension, weight=w=mg and buoyant force=F_b. I introduced symbols for...
I have studied a few online sources about static equilibrium in a mechanical system. My overall understanding is that for an object to be in static equilibrium, two following conditions have to be fulfilled:
1) Vector sum of all external forces that act on body must be zero.
2) Vector sum of...
Hello,
I am currently reading the about the topic mentioned in the title of this thread. In my textbook, the author gives the example with the wine-bottle and it's holder (I attached a photo). In this example, the author states that in order for this to be in static equilibrium, the second...
Homework Statement
In Figure, a 103 kg uniform log hangs by two steel wires, A and B, both of radiuses 1.20 mm. Initially, wire A was 2.50 m long and 2.00 mm shorter than wire B. The log is now horizontal. What are the magnitudes of the forces on it from Wire A, and Wire B?
Ysteel= 2.00*10^(11)...
Homework Statement
A painter (mass 61 kg) is walking along a trestle, consisting of a uniform plank (mass 20.0 kg, length 6.00 m) balanced on two sawhorses. Each sawhorse is placed 1.40 m from an end of the plank. A paint bucket (mass 4.0 kg, diameter 28 cm) is placed as close as possible to...
Homework Statement
we know that, every force systems can be generally replaced by a resultant force(R) and a couple(M) at a point O and the position of point O is optional.
but magnitude and direction of M is dependent to this point while magnitude and direction of R is independent.
In static...