Hooke's law Definition and 257 Threads

Hi guys. Hooke's Law is stated as: Stress is proportional to strain within elastic limit (or load proportional to deformation). But I can't really figure out why this happens. I mean what is the cause of this proportionality?

Homework Statement A spring with a spring constant of 1.8 X 102 N/m is attached to a 1.5 kg mass and then set into motion. a. What is the period of the mass-spring system? b. What is the frequency of the vibration? Homework Equations The only one that comes to mind would be Hooke's Law...

A graph shows the Force of a spring (y axis) against Displacement (x axis) in a linear function. An obvious point for the gradient is the point (0.5 metres, 140 Newtons). What is the spring constant and how much energy is stored in the spring when it is compressed by 0.5 metres? Hope the...

Homework Statement Hooke's law describes a certain light spring of unstretched length 35.0cm. When one end is attached to the top of a door frame and a 7.50kg object is hung from the other end, the length of the spring is 41.5cm. a) Find its spring constant. b)The load and spring are taken...

I'm just having a bit of trouble understanding when to use F=kx and when to use W=.5kx^2 . I understand that Hooke's law is for the spring force and elastic PE is obviously for work, but you could use either one of these equations to solve for, for example, k: When solving for the spring...

Hi I need some help with question 4 and 7 on the attachment. How do you do them? Thanks!

Is it possible to use a spring which does not obey hooke's law as a force gauge? If so, how? also If you incline the plane so that the block starts to move do you expect it to slow down and stop? If so why? If not, what do you expect? How can you measure the kintetic friction coefficient using...

Homework Statement This is the problem; it's multiple choice. When you try to stretch a bungee cord a distance x, it resists with an opposing force of the form b x2, where b is a constant. If b is measured to be 6 N/m2, how much work does it take to stretch the bungee cord a distance...

Homework Statement A force of 720 N stretches a certain spring a distance of 15 cm. What is its force constant? If a 60-kg mass is hung on it, how far will it stretch? Solving for Force Constant given: F (Restoring Force) = 720 N ΔL (spring's elongation) = 15 cm x (1 m / 100 cm) = 0.15 m k...

Homework Statement A tiny sphere with a charge of q = +8.8 µC is attached to a spring. Two other tiny charged spheres, each with a charge of −4.0-µC, are placed in the positions shown in the figure, in which b = 4.1 cm. The spring stretches 5.0 cm from its previous equilibrium position...

Homework Statement Hooke's law describes a certain light spring of unstretched length 33.0 cm. When one end is attached to the top of a door frame, and a 5.80-kg object is hung from the other end, the length of the spring is 42.50 cm. (a) Find its spring constant. (b) The load and the...

Homework Statement When a 2.90-kg object is hung vertically on a certain light spring described by Hooke's law, the spring stretches 2.93 cm. (a) What is the force constant of the spring? (b) If the 2.90-kg object is removed, how far will the spring stretch if a 1.45-kg block is hung on...

Homework Statement A wire of length L, Young's modulus Y, and cross-sectional area A is stretched elastically by an amount ∆L. The restoring force is given by Hooke's Law as k∆L. b. show that the work done in stretching the wire must be: W = (YA/2L) x (∆L)^2. The Attempt at a Solution...

Homework Statement Question is in attachment Homework Equations The Attempt at a Solution I mananged to find the acceleration up the slope but cannot get any further than this? - can someone please give me hint; push in the right direction Thanks :D

I am working on a theory and this thing is bothering since the past few hours... When we write down hooke's law that is d{2}x/dt{2} = -kx We write down as x as the displacement from the mean position given that the mean position coincides with zero... Now let's suppose that i have a 3D...

Following a discussion in this forum, I have a question: Is it possible to derive Hooke's law from first principles? I think a purely electrostatic model is not adequate: Earnshaw theorem would imply there's no "relaxed" position. Also, electrostatic forces get weaker with increasing...

Homework Statement In a pole with dimension lo=5m and section S=20 cm square acts the force of F=20Kn vertically downwards . How long will it go downwards, ---- thus delta l is needed Homework Equations I have delta l /lo =1/ EY *F/S The Attempt at a Solution I know the...

What are the Modern day applications of Hooke's Law?

hooke's law and shm help please Homework Statement a 4 kg mass is placed on a spring (k = 40n/m) which hangs vertically. the mass is allowed to oscillate in shm. the maximum distance the mass travels in anyone direciton is 30cm Homework Equations k = 40 n/m distance = 30 cm mass = 4...

Ok I wan't to start by saying I'm in a ridiculous solid state physics class where the stuff we are learning is either poorly explained by our textbook or even non-existent in the text. My teacher asked me the following question ... A single cube-shaped crystal of a simple cubic metal with face...

I was told that Hooke's Law (F=-kx) only accounts for small displacements. But for some objects the displacement can be greater than with others. I was wonderinig which quality of the objects is responsible for this?

If I'm given a set of data such as... Mass(kg) Spring Length(cm) 0.0 15.7 1.0 16.5 2.0 17.8 3.0 19.3 and so on... How do I determine whether or not the spring is obeying Hooke's law? I'm not sure what k is equal too. And is 15.7 the...

Problem) A coil spring has a spring constant of 54 N/m. If the full length of the spring is 35 cm when a 1.0-kg mass is hung from it, what is the equilibrium length of the spring when the 1.0-kg mass is removed? I have absolutely no idea how to even start this problem; and I know I can look...

Homework Statement A mass of 1.0kg is attached to a spring obeying Hooke's Law F = k.s, where F is the force applied and s the spring extension. The spring constant, k is 50 N/m. The spring and the object lie on a surface tilted 45 degrees with respect to the vertical Neglect friction and...

Homework Statement A block with mass M rests on a frictionless surface and is connected to a horizontal spring of force constant k, the other end of which is attached to a wall. A second block with mass m rests on top of the first block. The coefficient of static friction between the blocks is...

If I have a spring with a load and I oscillate it freely, applying hooke's law, TOP: GPE+EPE(Given by area under F-x graph) Equilibrium:KE (No EPE since x=0) Bottom:EPE Only Since energy is conserved, I have to assume that the extension (actually compression) at the top is less than...

Homework Statement A 50 kg traffic light is suspended above an intersection by a continuous steel cable. The cable has a diameter of 1.0 cm, and the light is depressed 12 degrees below the horizontal. What is the percentage increase in the length of the cable due to the mass of the traffic...

[SIZE="4"][FONT="Book Antiqua"]I did a Hooke's Law lab in class last week and one of the post-experiment questions asks to explain why the graph made should be a straight line and what should the slope and y-intercept be in terms of quantities in this lab? I know that Hooke's Law demonstrates...

Homework Statement It takes 3.23 J of work to stretch a Hooke's-law spring 12.1 cm from its unstressed length. How much extra work is required to stretch it an additional 5.76cm. Answer in Joules. Homework Equations F= -kx W= FD The Attempt at a Solution At first, I try using...

Homework Statement A massless spring of length 0.260 m is in its relaxed position. It is compressed to 68.0 percent of its relaxed length, and a mass M=0.240 kg is placed on top and released from rest (shown on the right). The mass then travels vertically, taking 1.60 s to reach the top of...

Homework Statement "A Daredevil plans to bungee-jump from a hot-air balloon 65.0 m above a carnival midway. He will use a uniform elastic cord, tied to a harness around his body, to stop his fall at a point 10.0 m above the ground. Model his body as a particle and the cord as having...

Homework Statement The left end of a spring is attached to a wall. When Bob pulls on the right end with a 200N force, he stretches the spring by 20cm. The same spring is then used for a tug-of-war between Bob and Carlos. Each pulls on his end of the spring with a 200N force. How far does...

Homework Statement An automobile air bag cushions the force on the driver in a head-on collision by absorbing her energy before she hits the steering wheel. Such a bag can be modeled as an elastic force, similar to that produced by a spring. Calculate the effective force constant k of the air...

Homework Statement A 2kg mass and a 3kg mass are on a horizontal frictionless surface, connected by a massless spring with spring constant k=136N/m. An 18 N force is applied to the larger mass. How much does the spring stretch from its equilibirum length? (answer in cm) Homework Equations...

Hi I am new to this forum I am currently doing year 11 physics at school nothing to complicated. now i have an assignment which i need to determine the length of the extension for a bungee and I am going to drop it from a certain height now i have the spring constant of my bungee and can figure...

A person is going bungy jumping. there is 2 kinds. Wet and Dry. in wet the person is submerged to a depth of about 1m. in dry, the person fall ends just above the surface of water. In one case, the bridge os 43m above the river and in the other case its 71m above the river. Participants jump...

Homework Statement http://img529.imageshack.us/img529/3814/hookes.jpg Assuming spring constant for system A (left) is k Then system B (middle) is k/2 and system C (right) is 2k http://img15.imageshack.us/img15/7238/87792676.jpg How about this system? Thanks for helping...

Do bungee cords and/or surgical tubing follow Hooke's law (F=-kx)? If not, are there any equations that give force in relation to length? If I was to numerically test for change of length by hanging weights off of each elastic, would it be possible to derive an equation according to the...

Homework Statement A body of mass (m) is suspended from a spring with spring constant k in configuration (a) and the spring is stretched 0.1m. If two identical bodies of mass (m/2) are suspended from a spring with the same spring constant k in configuration (b), how much will the spring...

1) A 28.86 kg child bounces on a pogo stick. The pogo stick has a spring constant 18016 N/m. When the child makes a nice big bounce, she finds that at the bottom of the bounce she is accelerating upwards at 4.802 m/s2. How much is the spring compressed? Given: Mass of Child: 28.86kg Spring...

Homework Statement http://i568.photobucket.com/albums/ss125/NakedNoodles08/GraphsandData-1.jpg Hello Physics Forums, i stumbled upon you guys when i stumbled within my physics work. The problem i am to put forth revolves around Hooke's law. I am conducting an experiment on Hooke's Law...

I'm talking about just any kind of F = k.x spring, with E = 1/2 k x ^2. Why can doors be closed by something that appears to have no energy source? Why can automatic guns reload requiring a battery source? (okay, maybe a bad example because they use the gas produced).

1. http://www.prep101.com/MCAT/102MCATPhysicsAnswers.pdf Numbers 4 7 and 14 2. As you can see the answers are already available, I'm just having trouble trying to get to them. 3. For number 4 I've tried plugging in the k value (8000) and distance (.05) into get a force value...

Homework Statement I'm not sure if this should be in this thread of the calculus one as it involves a bit of both. Basically I have to to make a question up that applies Hooke's Law. The only other condition is that k (the spring constant) must be equal to 20N/m. It should involve integration...

Hey there, I have a paper on “Hooke’s Law” due in soon and have ran into a few problem’s when writing it, first of dose anyone know...  How to find force constant?  How to find slope with units?  How to find % error? If you know any of the above, I would deeply appreciate the...

Homework Statement See attachment (titled "Statement.jpg") Homework Equations F = ma F = -kx U = K = (1/2)kx^2 I'm assuming there are more... The Attempt at a Solution My first attempt at this soultion was to use energy methods. The force applied for some time t0 will...

Homework Statement http://pyrofool.googlepages.com/lab25.gif A 2 kg mass and a 3 kg mass are on a horizontal frictionless surface, connected by a massless spring with spring constant k = 140 N/m. A 15 N force is applied to the larger mass. How much does the spring stretch from its...

Homework Statement A 70 kg bungee jumper leaps off a bridge. She is tied to a 12 m long bungee cord and falls a total of 31 m. Calculate: a) the spring constant of the bungee b) the maximum acceleration experience by the jumper Homework Equations F = kx Eg = Ee where g is...

The problem: See attachment for figure. (1) A rope with a spring constant k is stretched by a force F.The length of the rope is l (including the deformation). (2) A force mg is then applied at l/2 on the rope. This results in a height difference between the highest (and unchanged point) and...

does plywood follow hooke's law? is the young's modulus for plywood constant across the beam? :) and if u have any other hints with deam deflection I am willing to have them :P thanks!