Lever Definition and 170 Threads

Everyone knows about the law of the lever, in order for a see-saw to balance the torques must cancel each other. The question is, how fundamental is it? Can the Law of the Lever be derived from Newton's three laws or is it a fundamental law in its own regard? Some may say it stems from...

Homework Statement A board is set on top of a scaffolding, with dimensions as shown in the diagram. The board weighs 15 kg. A man weighing 70 kg stands on the board as shown. How far out can he stand before the board falls? Homework Equations Torque: \tau = rFsin(\theta) Force due...

Hi Guys, How much force will I need to lift 5000 kg block and how much force will be acting on the pivot point? I know how to calculate a normal lever but couldn't find any formula for lever with load evenly spread as per the attached diagram. see the attached diagram Thanks

Homework Statement Calculate the velocity ratio of the attached lever. Homework Equations Velocity Ratio = Distance moved by effort * Distance moved by load The Attempt at a Solution Ok I'm having some confusion over this question. I cannot figure out whether the 'Distance...

Why is it easier to push a load on a wooden crate on wheels when you are nearer the load and the lever is shorter and at a sharp angle compared to pushing a load with the lever lengthened and at a more relaxed angle with your body further away?

Homework Statement The 200Kg Crates are placed on a hydraulic lifting beam: (Diagram attached) A. State the order of lever used here B. Calculate the effort required to lift the load C. Calculate mechanical advantage for this system D. Calculate the velocity ratio for this system. If the work...

Is the lever formula ##F*a=Q*b## or ##Q*a=F*b## is it the same thing ? thanks

If I have a 10 foot long lever and the fulcrum is 1 foot from the end, if I place 2000 lbs. of force on the lever, what will be my "force" or torque at the end of the lever? And, very important, how much distance will the tip of the short end of the lever move up if the long end of the lever can...

Hey, I'm looking for an explanation of the why we observe T = F * d In the sense of two people applying a force to a lever arm and the person closer to the pivot point requiring more force to keep the torque in equilibrium. I can only find explanations in the sense of work and energy...

Homework Statement I have a situation a shown in the diagram below. A lever with a gas compression spring opposing it's turning. I want to find the force acting on the spring, F1, for a given inital force @ F0. [PLAIN]http://img18.imageshack.us/img18/9830/lever01.png Homework...

Is it possible for a lever to change from one class to another during its rotation (e.g. it starts out as a third class lever and ends as a first class lever)?

Homework Statement If a lever has a mechanical advantage of 0.5 - does this mean the input force is not amplified but halved? Homework Equations The Attempt at a Solution

Homework Statement If the mechanical advantage of a lever is, let's say, 10; the forces pushing down on the effort arm equate to 100kg and the forces pushing down on the load arm equate to 1000kg and the lever itself is 5 meters, how do we go about finding the individual arm lengths (i.e. the...

Homework Statement Calculate the effort required to lift the load. Homework Equations F=mg large distance × small effort = small distance × large load The Attempt at a Solution The load of the crate= F=mg F=200*9.81 F=1962N large distance × small effort = small distance...

Could someone please help me on this question. I do not really understand how to use the lever rule. Attactched is an example.. Thanks very much

Homework Statement 1962N Load 5 m from effort (hydraulic ram) and fulcrum 1m from effort. Calculate the Velocity ratio, if work input is 3000j calculate work output. Homework Equations VR = distance moved by effort / distance moved by load effort = 11772N MA = load / effort =...

Homework Statement Calculate the effort required to lift a load of 1962N using a third order lever with load 5m distance from effot and fulcrum 1m distance from effort. Homework Equations i used the following, large distance x small effort = small distance x large effort The...

Please forgive my ignorance, math was never my strong suit. But I have a question that has been bugging me, and I can't seem to figure it out, and thought perhaps that someone here could easily answer my question. I am a fly fisherman, and have been investigating certain claims regarding a...

I am looking at building a pair of third class levers out of materials found at the local hardware store to lift up some 500lb and 1500lb hulls. I have systematically gone through every option available to move these hull pieces out of the mold and I'm left with two: 1) Modify an "off the...

Homework Statement 3rd class lever 5m distance from load to effort and 1m distance from effort to pivot. Load = 1962 Effort required to lift load = 11772N MA = 0.16 or 1/6 ( so there really is no MA) Calculate the velocity ratio of the system ? Homework Equations I have...

Homework Statement We have a lever system. The end of the left side is a distance w1 from the pivot. The end of the right side is a distance w2 from the pivot. When no masses are attatched the lever is touching the ground on the left side. We place a known mass called m1 on the far left side...

Point A Point X 11 pounds 5 inches 5 inches ↑ 5 inches 5 inches _________________________________________________________________ 2 pounds 8 pounds ↓ ↓ Assume the horizontal line is a rod that is 20 inches long. The 11 pounds upward force is from a cable tied to...

Firstly, this is a great forum! Maybe this is more of a mechanical engineering question, but ... Can someone help give me some examples of non-linear levers? I want to be able to stretch a rubber band with factored-increasing force. Like a reversed camber on a compound bow. I hope I...

Hello I am trying to design a force balance lever system. Basically the initial state will in a force balance equilibrium. That is, there will be a mass m placed onto of the capacitor plate to keep the lever balanced. I will then ramp the voltage of the capacitor up, causing a force of...

My question is: How do you calculate torque when the lever arm is segmented? I have drawn a simple diagram to try to explain what I mean. Does the fact that the weight is now closer to the axis shorten my lever arm, or is the lever arm = D due to the fact that 10lbs is still being applied to...

[PLAIN]http://img444.imageshack.us/img444/8218/diagram.gif to calculate the torque (N*x) which one is correct? the one on top, or below.

[PLAIN]http://img20.imageshack.us/img20/7673/lever.gif I've come upon this phenomenon that as you shift the load left, or right, or anywhere along the lever, the intersection of the directions for the contact force due to the wall and the tension from the string will always be directly above...

So I have a simple lever that is connected to an extension spring. When the extension spring is exteneded it applies a force of 40lbs on the lever. The lever is 3 feet long and the pivot point is 1 foot from the top and 2 foot from the bottom. The lever weighs 2.1 lbs and has a 3lb weight...

I am redesigning a bicycle wheel quick release lever for a design project. I am trying to put together a force diagram as part of the project and I need to know the average force someones hand could apply to the tip of the lever to calculate the force exerted on the locking mechanism. Could...

Homework Statement If a torque of 55N.m is required and the largest force that can be exerted by you is 135N, what is the length of the lever arm that must be used? Homework Equations Lever Arm=(r)(sin) Torque=(Force)(r)(sin) The Attempt at a Solution To be honest, I'm stumped

Does anyone know of anything that flips a little lever when you send a current through it, then flips it back when you stop sending current? Something like this: _____ No current: _/ _ Current: \_____ _____ No current...

I have a doubt about hydraulic lever if a force f1 is applied at piston of smaller area a1 then pressure is transmitted to every part of fluid due to aplication of f1 smaller piston move down and piston at other end move up does the moving up of second piston have any effect on...

Part 1 - Question About Torque Of Lever Arm in a 1st Class Lever Homework Statement A little while back I posted a question about incorporating the torque of a uniform mass and dimension lever arm into the principle of a 1st class lever. Here is the thread for reference...

In trying to solve a problem, I was using the simple F1D1 = F2D2 as the balance point of a lever. My limited physics knowledge knew no better. My hypothetical involved using the "short side" of a lever to lift a weight on the long side of a lever. After thinking about it... I realized I...

Homework Statement The lever BCD is hinged at C and is attached to a control rod at B. Determine the maximum force \vec{P} which can be safely applied at D if the maximum allowable value of the reaction at C is 500 N. Here is a picture of the problem. It is number 4.20. "[URL...

Hello, I have a question about a see-saw / lever problem. Does this configuration I have shown here allow me to treat the system like a regular lever if I make the downward force at the horizontal point from the center to be the cosine of the angle? In this example the downward force on the left...

http://img16.imageshack.us/img16/7028/tempqk8.png This is the second time I'm posting this; last time I was told that it was not explicit. The image consists of 3 masses, m1, m2 and m3, out of which m1 and m3 lies at rest while m2 is in motion in the direction of the arrow. When m2...

We have a seesaw arrangement, a mass m3 supports the fulcrum, we have mass m2 on one end, and a mass m1 fall on the other end with velocity v. Considering the distance between the fulcrum and m1 is d and that of m2 is r, what will be the momentum distribution?

lets say we have a balance with these masses attached: 1) 11g mass at 7cm to the left of the fulcrum 2) 32g mass at 16cm to the left of the fulcrum 3) 11g mass at 7cm to the right of the fulcrum 4) 32g mass at 16 cm to the right of the fulcrum This balance should be...

Hi all, I thought of an interesting problem that I don't know how to approach (it's been 8 years since my last physics class in undergrad studies). Here is a crude depiction of the problem: _____■_____ _____●_____ lever ....↑....... ground Assume the cube and sphere...

I have a simple lever with two points of equal force, each at a different distance from the fulcrum. --- What I want: As the arm turns, one point of force moves at a faster rate than the other. --- What I DO NOT want: One point of force having a mechanical advantage over the other...

hi.. i have a problem that i need to solve.. in the attached mage, there is a submerged object in water cousing na upward lift force of 100kg. above it is a lever with a weigh attached to it weighing at 90kg. wll this weight difference be enough to move the metal wedge from point a into point...

Right angle lever paradox. This paradox has long been a thorn in the side of relativity. In 1909 Lewis and Tolman analysed the behaviour of a right angled lever with balanced forces with relative motion. They noticed there would be a potential imbalance as the arm parallel to the direction of...

Hi guys. I haven't had physics in a couple of years and I'm trying to study for the MCATs. I've always had trouble with levers so I would really appreciate it if I could get some help. In particular, the following scenario confuses me: Say you have a man standing on a board, the fulcrum is to...

hey i have got to make a scaled model of any mechanism that we see around(or maybe we don't sometimes) in the machine shop in under 3 days as our summer training project. we are provided with all the raw stuff and machines that one usually sees in machining shop. i have decided to make a crank...

Homework Statement A lever of length 3L can rotate freely around a horizontal axis O. The end of each arm "2L" and "L" of the lever has one mass : "4m" and "9m" , respectively. Find the velocity of mass "9m" at the bottom. Consider that the lever was initially at rest in the horizontal...

Homework Statement I have a lever problem, i wish to find the force on the fulcrum; how do i determine this force? http://www.UploadYourImages.com" Fin = 80 N Fout= 21.5 N (yes, usually a lever is supposed to increase your power, but it represents a rowing oar)

Hi, if you have a see saw with equal weights on each side, but it is at a slight angle; how do you calculate the force in Newtons on one side which is making it balance? Please see the picture: http://img408.imageshack.us/img408/6870/questionlw6.gif Thankyou

My problem (trying to help an ay last keen son)-a lever 5m long, a weight of 300kg, a force of 100kg. The question says describe? I am trying to work out the distance from the end of lever to fulcrum or in other words where the fulcrum should lie. tried formula which has gone to...

I can't figure this problem out and i don't know where to start. A young boy(50kg) wants to lift a boulder with a mass of 2500kg. He can wedge a board under it so that from the boulder to a pivot/fulcrum is 0.6 meters. How long does the other end of the board have to be for the boy to lift...