Weight Definition and 1000 Threads

Can you pull down/hold more weight than your body using your muscles? Imagine a 1 to 1. One side is suspended 190 pounds, the other is me, 175 pounds. Can i, using my muscles and standing on the ground, hold that suspended weight off the ground? I understand if i lock out my arms and...

For practice I did the following problem: Solving this problem mechanically was simple enough using the following force diagrams: Then $$F_{net_M} = T - Mg = 0$$ Due to the stationary condition $$T = mg$$ and $$F_{net_m} = T = ma_c$$ $$T = ma_c$$ Because centripedal acceleration is...

Hello, I am interested in making an RC plane as illustrated. Some questions: 1. Given that the build material of the plane will be 3d printed out of PLA and I want the wingspan to be between 1.2m - 1.35m ideally. How can I calculate the minimum wingspan/wing shape/wing area to carry a payload...

I found the density of carbon and iron: ρ_fe=7.87 g/〖cm〗^3 ρ_c=2.26 g/〖cm〗^3 Using equation 2: atom density of iron and carbon N_fe = 8.48e22 cm^-3 N_c = 1.13e23 cm^-3 Using equation 1: macroscopic scatter and absorption cross sections of iron and carbon Σ_a,fe = .217 cm^-1...

how do I calculate how much force is needed to lift a horizontal metal tube to a vertical position. The metal tube is 25 feet long, weighs 300lb and and pivots 5 foot from the bottom. I will be using a hand winch and the cable attaches at the bottom of the 5 foot end of the tube.

A man and a boy hold opposite ends of 8m long pole which is horizontal. A mass of 200 kg is tied to the pole. If the man is to support four times as much weight as the boy where along the pole must the weight be tied? Can someone please help

The force exerted downwards on the scale by the chain when it is kept on it would be Fg= Mg =λLg where λ is the linear mass density However when the chain is dropped onto the scale it exerts an additional force due to its change in momentum The force exerted by each part of the chain would...

Hello everyone. I'm building myself a half-rack for weight lifting that included 2 overhung support beams above from which to hang a safety strap incase of a failed lift. They are made from 2x3x.125 steel tube (they're Oriented with the 3" vertically). The tube are overhung by 21". How much...

Hi everyone! I regularly use the forum to learn but never registered to post anything, as I have nothing to teach really… But today I have a question regarding the law of conservation of energy that I can’t find the answer to, and maybe someone will help me understand: (I’ve attached a drawing)...

My solution is However can someone explain in detail why will be equal to the weight? and why does it have to be multiplied by 6?

I 'get' how the gyroscope works, but I only understand it mathematically. I understand that because Torque = r x F, so the direction of the torque is such that it can change the direction of the Angular momentum, resulting in the gyroscope precessing. However, I just cannot visualise how this...

Hi, This has long been in my head, I've seen it work out in reality, but I have no idea about the forces involved in this. As I don't have an engineering degree or mathematical knowledge in automotive engineering, I've come here for help. Sorry if I've used some terms where they do not fit, as...

I read about a proposal for storing potential energy by hoisting heavy weights that can be dropped when needed to generate electric power. So using the numbers from a hydraulic turbine from Hoover dam, how heavy would a hanging weight have to be to generate 178,000 horsepower as it descended...

I’m trying to calculate the weight I have to support at one end of a pipe with flowing water. So suppose you had a water pipe that extended from the ground upwards some distance away both horizontally and vertically, i.e., at an angle. Normally, you don’t have to worry about this issue because...

Hi, I'm working on a project to see if deliveries, pick ups, or both combined are better for the environment / more energy efficient / more time efficient. For example, (a) everyone collecting from a farm by bike, (b) vans bringing to supermarkets and then people collecting from supermarkets, or...

I am interested to compare two scenarios relating to grip strength and how much horizontal pressure will be required to hold the weight. Scenario 1: You have a 20kg weight plate in one piece. You hold the plate between your fingers. Scenario 2: You are holding a small 2X4 block of wood with a...

a. To find the speed, I need to find the height where the cords first become loose, which is when the cord is 25 m long. $$h=30-\sqrt{25^2 - 5^2}$$ But the teacher's working is ##h=30-\sqrt{25^2 - 4^2}## How to get 4? b. My idea is to use Newton's 2nd law so I draw free body diagram of the...

Hi guys, I don't have much knowledge of physics sadly, and I want to build a machine that can spin a disk. My question is - How can I know the weight I can spin on a motor? I need to be able to spin around 5-6kg, for 350 RPM, and I'm not sure I'm aiming for the correct motor. I'm thinking of...

Hello, I need to scale down a human model by 1:20 i.e, i need a human model of 9 cm height scaled down. Help me calculate the weight of the 9 cm scaled down human model. Regards, Viky

Could I please ask for help with the following question: A uniform lamina of weight W is in the shape of a triangle ABC with AB = AC = 2a and the angle BAC equal to 2ᾳ. The side AB is fixed along a diameter of a uniform solid hemisphere of radius a. The plane of the lamina being perpendicular...

What does it mean that the relationship between material mass and weight is constant and proportional? Hi! Yes, another question... I have many doubts. :) I hope someone can help me with this apparently very basic doubt, but I feel like a stupid monkey trying to join two sticks to reach bananas...

I don't see how isolate m or M. That is, how to get rid of <v^2> which is how I wrote the average of v2

During the day, I am between sun and earth. During the night, I am behind the Earth if I'm looking from the sun. So its Day: sun-me-earth night: sun-earth-me So the forces of gravity from sun and Earth add during the night, but during the day, the sun attracts me away from the earth...

All the popular definitions of 'air pressure' that I have seen say: "air pressure is the weight of the column of air above you". This seems misleading to me. - -...

Been thinking about mass today and came up with a question. Why is that objects on this Earth describe its weight in Kg, g, mg, Mg? IE 2.2Lbs is 1Kg. So why do we name the 1Kg to be mass, but the 2.2Lbs we call weight. Both have to be a unit of force if there is a conversion factor between the...

BACKGROUND: I'm thinking of building a flat bottom Jon boat. We don't have room for a boat trailer so I want to load the boat on top of our 2019 Honda Odyssey van. Without a trailer, the boat can be stored on a side against our hollow tile wall. The dimensions of the boat will be: 12 feet...

I have attempted to plug in grams, kiliograms, and even pounds but it was wrong.

I remember being told that heavier things fall at the same rate as lighter things when everything else is equal. But this guy does a demonstration of a Xenon balloon falling faster than a Neon balloon. Why? Also an overloaded plane may not be able to fly, but it has the same aero dynamics, it...

Hello everyone I am trying to solve the following question from the book Analytical Chemistry 7th edition by Gard D. Christian - Page 164 Example 5.17 My problem is when I calculate the molecular weight of Pb(NO_3)_2 I get 331.2 g/mol but in the book they get 283.2 g/mol . Could you explain...

I have the following table. I would like to know how to give an weight to the "12 Month Median Ranking of Opponent" so it changes other two columns depending on how high/low the ranking is. To put this into perspective, this is regarding tennis players. On the spreadsheet I can have two players...

I just would like to check if my corrections to each of the wrong options are right. A) & B) elastic potential energy greatest at B, not at A or O, based upon Eq.1 D) Since dU/dt = 0 at O because O is at equilibrium where no change of spring length. E) At A, dU/dt = -kx. At B, dU/dt = -kx = -kx...

This is an issue I've been stuck on for about two weeks. No matter how many times I take this derivative, I keep getting the same answer. However, this answer is inevitably wrong. Please help me to understand why it incorrect. To start, I will define an input matrix ##X##, where ##n## is the...

Hello! Now what I've done is first calculate the acceleration. a = 1,962 m/s^2. Than I tried looking at the solution simply through the Newtons laws (or axioms I don't know how to say it in english). Since the elevator is moving through the air the gravitation constant has to be taken into...

Hi can someone give an hand on understanding how to handle such kind of problems ? can't come up with a valid solution. if i do ##\frac {0,56}{2*14.00}## do i get the molar fraction of nitrogen?

I am building a plant rack. Because of size restrictions, I must use angle iron and I want to use aluminum angle because of weight. I am looking at aluminum angle (L shaped) for the shelf brackets. The aluminum angle is 1" and 1/16th thickness, 24" long and screwed into wood. Each angle will...

This is from Halliday et al Physics 4e, p9, sample problem 3. Problem: My question: Why do the authors say that the weight of the cat has 1lb uncertainty rather than 2lb? Isn't it between 127.5-119.5=8lb, and 10lb, hence 9lb+-1lb ie uncertainty of $$\frac{2}{9}\times 100 = 22\%$$ rather...

Hey! :giggle: Calculate the node $x_0$ and the weight $a_0$ of Gauss Quadrature so that $$\int_0^1w(x)f(x)\, dx\approx I_0(f)=a_0f(x_0)$$ where $w(x)=1+\sqrt{x}$. I have done the following: The Gauss quadrature formula with $(n + 1)=1$ node (i.e. $n=0$) integrates polynomials of degree $2n +...

I realized that the tension in the rod is not uniform and found it to be ##T = Wx/L## I found this by splitting the rod into two sections one of length ##x## and the other of length ##L-X## where x is the length from the base of the hanging rod To find the total elongation in the rod I...

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Engineers are confronted with two apparently true but contradictory statements for airplanes in flight: a) Lift must equal the weight of the airplane (Lift = Weight), based on Newtons 2nd Law of motion (i.e. Force = ma); where gravity is used to calculate weight (i.e. Weight = mass x...

So here's what I've tried: force from part (a) / weight = 499.649N / 15kg = 33.310 force from part (b) / weight = 10.511N / 15kg = 0.701 Apparently this wasn't correct. What am I doing wrong? I feel like I'm missing the obvious.

Below I've attached the question - I don't know why this question is so difficult, perhaps I missed a lesson or such, however I've Benn working at it for ages and got nowhere...

Since we have a .3% change in weight (force) for weights that are lifted from locations on earth, are their rules that focus on mass or weight with olympic weightlifting? In other words, if i wanted to break the world squat record, wouldn't i go to the equator to try and break it, giving that...

<mentor moved thread> Suppose humans could travel quickly through deep space and are in search of an earthlike planet. A perfect planet is found, with the exception that its mass is huge, such that a human weighing x EarthKilos on Earth (1 G) now feels like he weighs 3x EarthKilos. So the...

Since the "non-uniform" hypothesis I got confused about how to solve this problem... in which way could I find its center of mass, if its mass is not distributed uniformly? Another question I have with regards to this static situation is: is the beam placed horizontally? If not, how could I know...

I am trying to design a free standing stand for a pyrometer, which weighs 750g. The pyrometer needs to be 1.5 metres above ground level. The stand will be constructed entirely in steel. The layout of the stand is shown in the uploaded diagram Pyro_stand.gif. How can I derive expressions for the...

Hey everyone! Here is the problem I have been tackling but did not end up with the correct answer The extra red arrows I have labelled in myself and called these distances h1,h2 and h3. I assumed the pressure to be the same at levels A & B, hence i have established expressions for both of...

I'm having a hard time solving this problem since I don't really know how to apply the weight force of the trap door. Ideally, in order to find the contact force exerted by the rod, I would find out the weight force of the trap in the point of contact and then find its component radial to the...

This is my attempt of solving it