Static Definition and 1000 Threads

Homework Statement Use the integral form and symmetry arguments to compute the electric field produced by the following charge densities: (i) Point charge q, placed at the origin, in 3 dimensions; (ii) Point charge q, placed at the origin, in 2 dimensions; (iii) Point charge q, placed at the...

Constitution: Static or Living and in it means?? I was reading "The Original Constitution", by Robert G. Natelson. The work assesses Constitution and Bill of Rights in light of eighteenth-century law, minutes from the Confederation Congress, the original Articles of Confederation, Federalist...

Homework Statement A 45-kg crate is placed on an inclined ramp. When the angle the ramp makes with the horizontal is increased to 24 degrees , the crate begins to slide downward. What is the coefficient of static friction between the crate and the ramp? Homework Equations \SigmaF=ma...

A 736g uniform mass beam is used to suspend a sphere that weighs 5.25N. it is supported by an ideal rope attached to the wall, and one third the length along the beam (from the wall). The angle between the rope ans the beam is 51.0 degrees. a) draw a free body diagram b) calculate the...

What is the correct expression for the acceleration of a static test-particle in coordinate time according to the Schwarzshild solution? I am a bit confused. I would like it to be the same as classically, ## d\bar{v}/dt=-\frac{GM}{r^2}\hat{r} ##, but according to "reflections on relativity"...

Homework Statement A car can decelerate at -4.90 m/s^2 without skidding when coming to rest on a level road. What would its deceleration be if the road were inclined at 11° uphill? Assume the same static friction coefficient. Homework Equations Force of Static Friction / Normal Force...

There's a box sitting on a plank. The coefficient of static friction is 0.33. I want to figure out at which angle the box will begin to slide if the plank is tilted. I know the factors that come into play are FN, Fg or Fgx, and Fs. So far I have Fnet= FN-Fs-Fg =FN- μs-sin∅...

There's a box sitting on a plank. The coefficient of static friction is 0.33. I want to figure out at which angle the box will begin to slide if the plank is tilted. I know the factors that come into play are FN, Fg or Fgx, and Fs. So far I have Fnet= FN-Fs-Fg =FN- μs-sin∅ =cos-0.33-sin∅...

Homework Statement Pin C joins members ABC and CDE Homework Equations Sum of moments at a point = 0 Sum of vertical forces = 0 Sum of horizontal forces = 0 Weight of triangle acts as a force at its centroid (1/3) its length according to this figure. The Attempt at a Solution...

Homework Statement A .110-kg remote control 21.0cm long rests on a table, with a length L overhanging its edge. To operate the power button on this remote requires a force of .365N. How far can the remote control extend beyond the edge of the table and still not tip over when you press the...

An 6.40kg block rests on a 12.5kg block. The interface between the lower mass and the table is frictionless, but there is friction (static friction μs and kinetic friction μk) between the two blocks. A horizontal force F acts on the upper block and causes both blocks to accelerate. The...

If a curve with a radius of 89.0m is perfectly banked for a car traveling 71.0km/hr, what is the minimum coefficient of static friction for a car not to skid when traveling at 91.8km/hr? I figured out theta = 24. 03degs from the equations F(normal)*cos(theta) = mg and F(normal)*sin(theta) =...

Homework Statement Calculate the reaction MA http://alkaspace.com/is.php?i=134123&img=E-3.1.jpg Homework Equations The Attempt at a Solution First I have put the reaction By as an hyper static force. Then I found the deflection in B with the force By as a variable. vb=...

Homework Statement There is an initially stationary block of mass m on a floor. A force of magnitude 0.500mg is then applied at upward angle θ = 20°. What is the magnitude of the acceleration of the block across the floor if (a)μs = 0.630 and μk = 0.540 and (b)μs = 0.400 and μk = 0.330...

Hi there. I've got issues. Big ones. I need to simplify this crane structure, and calculate the strength on cilinder |c1c2| when applying a vertical load on the crane's hook. The purpose of this is to find how much of the strength is absorbed by the first cylinder (and possible the second one...

As an exercise in cosmology-fiction (I actually got curious about this from an actual cosmology textbook problem), taking into account the stellar nuclear reactions that involve the fusion of hydrogen into helium, what would (roughly) be the proportion (in mass) between Hydrogen and He-4 in a...

Hello everyone Just a quick question, hopefully someone could shed some light upon what I'm doing wrong here? I'm using ANSYS Workbench to apply a force to what is effectively a cantilever beam, fixed at one end, with a load applied at the other. To be more specific it is a spring strut of...

Homework Statement A coffee cup on the dashboard of a car slides forward on the dash when the driver decelerates from 48 km/hr to rest in 3.7 s or less, but not if he decelerates in a longer time. What is the coefficient of static friction between the cup and the dash? Homework...

The question is rather old but I am not sure if we have a final conclusive answer (I was not able to figure it out for myself, nor have I found consensus in the literature) 1) do free-falling charges in a static gravitational field radiate? 2) do charges at rest in a static gravitational...

Hi, I'm trying to model a compensation device in a hydraulic system. Basically, I have a closed pipe that contains a body of liquid (water glycol) and as time elapses this fluid is subject to a cooling effect. This results in contraction and hence a pressure decrease which is subsequently...

I have attached another diagram, and in the diagram I show a round piston with a 1 sq ft surface area pushing water through the pipe out into to open atmosphere at 14.7 psi at a constant velocity of 75 ft/sec. There is a vacuum behind the piston, and I have calculated a 37.9 psi dynamic pressure...

Homework Statement Two points charges A(+10. uC) and b(+40.0 uC) are placed .2 m apart forming line ab. Calculate the force experienced by a point charge C(+10.0 uC) placed on line Ab, .06 m from A Homework Equations F=kq1q2/d^2 The Attempt at a Solution First I tried making a diagram...

I've worked through this problem for a while now and can't quite come up with an answer. The problem is as follows: A block with mass 5 kg sits on an inclined plane of 30°. The coefficient of static friction is 0.1 between the plane and block. A force F is applied in the horizontal direction...

Homework Statement Attached is the picture of the problem and my free body diagram. The system is in equilibrium. Homework Equations Fy = 0 Fx = 0 The Attempt at a Solution I'm having trouble solving the two equations that I arrive with... I use +x to the right, and +y up...

Homework Statement What should happen to the electrons in a insulated metal object when a negatively charged plastic rod is brought near the insulated metal The Attempt at a Solution I thought the electrons will repel each other and the insulated object will move away from the rod...

Homework Statement I have a few problems that I found in my review package that I just couldn't figure out. I've been trying all day as I'm used to the normal F=kqq/r^2. These are higher levelled problems, but my prof says that they will be on the midterm which is coming up next week. If...

If the CMB is quantum fluctuations of the primordial universe, I would expect it to move, not be static like a photograph. Quantum fluctuations do not hold still, nor has time itself seem to have dilated to the point where it would look constant. Can somebody take a movie of it and see? All...

A Pitot-static tube connected to water manometer is used to measure the velocity of air. If the deflection between the two arms of the manometer is 12.4cm, determine the air velocity when the density of air is 1.25kgm-3 and the density of the water in the manometer is 1000kg/m3. I am not...

I have calculated a static contact stress of 670 N/mm2 using formula from Mechanical Engineering Design, Shigley, 5th Edition. My problems lies that there is no acceptance criteria. I'm using Grade 5 Structural Steel (yield~355 N/mm2). Previous threads have stated that a 2.5 * yield can...

The result I got seemed sort of messy and I'm not sure I've gotten the basic idea correctly, so I thought I'd make it sure. I think this was the easiest problem we had to solve for charge distributions and point charges and whatnot, so I know for sure I'll have to practice more if I made any big...

There's a popular experiment where you get two pieces of Scotch tape and label one top and one bottom. You attach them together on their sticky sides and then pull them apart and they will attract showing that you can get static electricity without friction. Anyhow, when I thought about it I had...

Homework Statement A column has the dimensions shown below... Column material properties: young's Modulus E = 200 GN m^-2 Yield stress = 140 MN m^-2 Homework Equations a) what is the minimum length of the column at which buckling is likely to occur? The...

Hey guys, Most physics or introductory electronics books that I have read begin the topic of electricity by introducing static electricity. The books introduce static electricity by either talking about the amber and the wool experiment or the glass rod and the silk cloth. My question is...

*** Title says static - need kinetic friction!Homework Statement Find the amount of kinetic friction. A block with mass of 0.422kg slides down a ramp from rest. Given: acceleration = 1.58m/s^2, mass = 0.422kg, theta = 29.0°, velocity two (end): 1.7m/s, and total time is 1.10s. I also need to...

I know static friction can cause an object to accelerate, but also decelerate. And i also know that static friction never cause energy loss, but I wonder when it causes an object to decelerate, its kinetic energy should decrease, so where is the mechanical energy gone? Has static friction done...

Homework Statement Which of the following statements are true about Fs, max in the equation mu=Fs, max/Fnormal? I. Fs, max is exerted perpendicular to the surfaces in contact. II. Fs, max represents the maximum value of the force of static friction. III. On a level surface, the magnitude of...

I know that lightning can, but look at the following example: A Van de Graaff generator can produce lots of volts. Lats say 100 KV for our purposes. Why doesn't this voltage kill you? Many people say that it doesn't have enough amps, but let's look at Ohms law: V = IR. I measured the resistance...

Does anyone know the name of a type of rock that gives off a static charge when hit, like struck with a hammer?

What is the physical difference between static and magnetic attraction?

In a project I'm working on at school I could only get static acceleration from the 3-axis accelerometer I have (MMA7361L). I used a simple set-up (4 pins: Tx, Rx, power and ground). As far as I understand, accelerometers are able to detect both types of acceleration but I don't know why I...

Homework Statement a 4.0kg block is held against a brick wall and is just kept from sliding down by the force F. The coefficient of friction is 0.35 between the block an d the wall. Find the normal force and the minimum force F that will keep the block from sliding. Homework...

Homework Statement A hiker, who weighs 985 N is strolling through the woods and crosses a small horizontal bridge. the bridge is uniform, weighs 3610 N, and rests on two concrete supports, one at each end. he stops one - fifth of the way along the bridge. What is the magnitude of the force...

Homework Statement In the following figure(one box on a table, m1, connected to a string that is on a pulley attached to box m2), m1=10kg and m2=4kg. The coefficient of static friction between m1 and the horizonatl surface is 0.50 while the coefficient of kinetic friction is 0.30. (a) If the...

You probably know how to bend water: Use a comb and rub it with wool (or just comb your hair) and hold it next to thin jet of water coming out of a tap. Here is a video: Comb with wool An explanation is offered here (the water molecule is polar). However, I remember my physics teacher...

Homework Statement A uniform rod AB has a length l and a weight W0. End A is in contact with a rough wall, but it is not fixed. A massless cord connects end B and is fixed to the wall at point C. The rod AB is now horizontal and the angle formed between the cord and rod is θ as shown in the...

ANYS Static Structural, How to simulate 'ground"? Hello all, first post. I'm having trouble simulating a fixed support in only ONE direction. For example, imagine a gigantic frame laid on the ground and you wanted to see the forces deflect from pulling up on one corner, (the ground...

This is the final question on a static equilibrium quiz i had today (physics 12). when comparing answers (as you tend to do after the quiz "did you get x for question y?"), half of my friends (all of equal ability in the course) got a different answer from me, and the other half the same. I am...

Homework Statement Refer to Figure 3. A steel box (250 mm x 250 mm x 250 mm) is placed at the bottom of a tank. If the pressure on the top surface is 10000 Pa, what is the water depth in the tank? Answer a. 1019 mm b. 251.02 mm c. 1269 mm water density: 1000 kg/m3 gravity...

Hi guys, I am University student doing a research on Static Shocks but i lived in the tropics and need to know more about the occurrence of static shocks in other climates such winter etc. Hopefully you can lend me a helping hand by completing my survey. THANK YOU...

1. A wooden block of mass 29.0 kg sits on a horizontal table. A wire of negligible mass is attached to the right side of the block and goes over a pulley (also of negligible mass and frictionless), where it is allowed to dangle vertically. When a mass of 15.5 kg is attached to the dangling wire...