Static Definition and 1000 Threads

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...

Hi guys, I need to be able to estimate the thrust that a turboprop propeller produces at sea level static. Say I have an 1100 hp pt6a engine and a 80 percent efficient propeller. I have seen formulas that calculate the thrust but you need to be moving. I want to know the static (your airplane...

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...

Homework Statement Find coefficient of static friction if shell starts to slip at θ = 60° known - θ unknowns - P, r, Normal force, weight Homework Equations friction = μ * normal force The Attempt at a Solution I do not know where to start. It looks like the picture wants you to...

I am working on this word problem, you can see from my attachment.. I want to make sure my body diagram is correct?

Homework Statement The attached pdf shows the whole problem. I have a deadline of Wednesday for this and am absolutely stuck! Homework Equations N/A The Attempt at a Solution I have figured out parts a, b, and d. I was wondering whether anyone can help or point me in the right...

[credit to wikipedia] So it would appear that the type 1 meissner effect allows for the localized increase of magnetic flux density (as the displaced field must go somewhere, the B field is somewhat larger at the surfaces of the superconductor then elsewhere, and in fact is a higher value...

Homework Statement Find stress or force in member AE Homework Equations torque = force x distance The Attempt at a Solution Solution out of book is 142 kN Attempts: Mb = -(200kN)(2.5m) + (.895AE)(5) + 510 = 111 Kn Mc = -(3m)(170kN) + (.895AE)(5) = 114 kN Md...

Homework Statement http://www.solutioninn.com/images/E-C-S%20%28808%29.PNG ignore the given FBD below the pic. Problem said that: there are 3 blocks like in the picture, with weight A = 600lb, B =150 lb, and C = 500. Find force P such that it will move block C. (everything is static...

Homework Statement In the figure below, the driver of a car on a horizontal road makes an emergency stop by applying the brakes so that all four wheels lock and skid along the road. The coefficient of kinetic friction between tires and road is 0.36. The separation between the front and rear...

Okay, I have read all the threads on this site that I could find about Bernoulli's equation and blood pressure, but I am still really confused, and the more I think about it the more confused I get. I get that bernoulli's doesn't take frictional losses into account, but at a short section of...

Homework Statement A 4.0 kg block of wood sits on a table. A string is tied to the wood, running over a pulley and down to a hanging object. The greatest mass that can be hung from the string without moving the block of wood is 1.8 kg. Calculate the coefficient of static friction...

A mass (m = 3 kg) is connected to a spring of constant k (k = 50 N/m), where the mass is connected at the top to a spring on a fixed incline. The coefficient of static friction between the mass and the incline is µ(subscript s) = 0.6 and the angle that the incline makes with the horizontal is...

A meat baster consists of a squeeze bulb attached to a plastic tube. When the bulb is squeezed and released, with the open end of the tube under the surface of the basting sauce, the sauce rises in the tube to a distance h, as the drawing shows. Using 1.013 × 1055Pa for the atmospheric pressure...

Homework Statement a. A uniform beam is hanging from a poing 1.00 m to the right of its center. The beam weights 140 N and makes an angle of 30° with the vertical. At the right-hand end of the beam, a 100-N weight is hung; an unknown weight w hangs at the left end. If the system is in...

Homework Statement See attachment. Homework Equations F = μN The Attempt at a Solution I attached the FBD I drew. I then did ƩFx = FA + FBcosθ - NBsinθ = 0 ƩFy = NA -W + NBcosθ + FBsinθ = 0 ƩMA = 19.5NB - 3.75W = 0 ƩMB = 3.75W - 7.5NA + 18FA = 0 FA = μNA FB = μNB θ =...

Homework Statement "The work done by static friction can be: a) positive b) negative c) zero d) nonnegative e) any of the above Homework Equations W=F*d F(friction)= μ *FN The Attempt at a Solution I thought the answer must logically be "c) zero" because static friction has no distance...

In a static equililibrium lab, what are some reasons why the sums of the forces and/or torques may not be equal to zero. The forces in N are very close to zero (as my professor said they should be) and the torques in N-cm are not anywhere close to zero. I know the torques are greater than their...

Hello, I was wondering if particles that have a set position such as for example particles within the Earth's core would experience a temperature gain due to gravity. If kinetic energy is applied to the particles in the air due to gravity, then kinetic energy should also be applied to...

Homework Statement A 224-kg crate rests on a surface that is inclined above the horizontal at an angle of 20.1°. A horizontal force (magnitude = 543 N and parallel to the ground, not the incline) is required to start the crate moving down the incline. What is the coefficient of static friction...

The problem: A car traveling on a flat (unbanked) circular track accelerates uniformly from rest with a tangential acceleration of 1.60 m/s2. The car makes it one quarter of the way around the circle before it skids off the track. Determine the coefficient of static friction between the car and...

Homework Statement So I have this lab I have to do about finding the relationship between static friction and normal force. So basically I need to find find how the Static Friction and Normal Force relate by doing a lab experiment. The materials I have are: Spring balance / scale Weights...

Hi, I am very confused. I have searched everywhere online and have drawn free-body diagrams, but I am still confused as to why static fricition, not kinetic friction, provides the centripetal force in a car moving in a circle. In addition, assuming that the centripetal force of a car...

Can someone please explain why static friction points in the same direction as the centripetal force for an object (like a box) on the flatbed of the truck that is traveling in uniform circular motion? Thanks in advance. :)

Homework Statement Show that the heat transferred during an infinitesimal quasi static process of an ideal gas can be written as dQ = (Cv/nR)(VdP) + (Cp/nR)(PdV) where dQ = change in heat Cv= heat capacity while volume is constant n= number of moles of gas R= ideal gas constant Cp=...

Homework Statement Suppose a block of mass = 10kg is on an incline plane that makes an angle = 45° from the horizontal. If a force of 10 N is being applied to the block, downward, and perpendicular to the surface, and the block is not moving, what is the static force of friction? What is the...

um, i placed my elbow on the table, and i think i mustve hit some ideal spot that actually caused a (static?) reaction up my lower arm. what i want to know is, what exactly it is, why did it happen, and why it only happens sometimes?

Static Equilibrium Problem Homework Statement A uniform bar of length 16 m and mass 8 kg is attached to a wall with a hinge that exerts a horizontal force Hx and a vertical force Hy on the bar. The bar is held by a cord that makes a 90 degree angle with respect to the bar and 45 degree...

Homework Statement A 62 kg crate is dragged across a floor by pulling on a rope attached to the crate and inclined 16° above the horizontal. (a) If the coefficient of static friction is 0.57, what minimum force magnitude is required from the rope to start the crate moving? (b) If μk = 0.31...

Homework Statement A uniform 7.7 m tall aluminum ladder is leaning against a friction-less vertical wall. The ladder has a weight of 291 N. The ladder slips when it makes a 59.0◦ angle with the horizontal floor. Determine the coefficient of static friction between the ladder and the floor...

Homework Statement This is not actually a homework problem but a design evaluation problem I have encountered. I am trying to solve for all the loads at the pins and have used WorkingModel to try and give me some quick answers. However, the solutions offered by the software do not make...

Homework Statement This is not actually a homework problem but a design evaluation problem I have encountered. I am trying to solve for all the loads at the pins and have used WorkingModel to try and give me some quick answers. However, the solutions offered by the software do not make...

I'm confused about finding the static pressure on a surface of a hypersonic vehicle. I know the inclination angle of surface 1 relative to the horizontal and I know all the aerodynamic characteristics of stage 1. With a calorically perfect gas assumption, gamma=1.4. I'm getting a little...

I'm a bit confused about the presence of a static friction FORCE. So here's the question: The potential for static friction is always present due to the nature of the contact surfaces and the normal force. But is a static friction FORCE always present or does it arise in response to...

Homework Statement A constant horizontal force F of magnitude 10N is applied to a wheel of mass 10 kg and radius 0.3 m. The wheel rolls smoothly and the acceleration of its center of mass is 0.6 m/s^2. What is that frictional force on the wheel?The Attempt at a Solution ok so the frictional...

Homework Statement In Formula 1 race, the cars approach curves from the outside, cut through to the inside, and then drift again to the outside (red path AA’ in the figure). However, the blue path (BB’) in the figure is shorter. Then why do not the drivers follow the shortest path? Give...