Weight Definition and 1000 Threads

Hello all, I devised a concept a couple years ago for renewable energy and hit a stumbling block: How do you insert a buoyant object into the bottom of a water column with the smallest amount of energy? Recently I revisited the concept and found some similar work online including this...

Hi I like to play basketball and am curious as to how much force is required to jump a certain height I have tried to calculate it but I get stuck at energy and am not sure how to find the force as it is difficult to measure without equipment and being very accurate and precise (unless there is...

Forces on a weight stack with the position of the pulleys so the weight is pulled up and the puller is moving a horizontally. Is it correct to use F=MG?

Hello I am using an rubber suspension component from Rosta, and want to calculate the deflection over a range of weights acting on a lever attached to the rubber suspension units. HOw do I convert static weight to Nm of force for determining the deflection of the units? thanks here's...

Homework Statement If we are simply standing on the ground will our normal force be always equal to our weight besides when we are jumping or when we land on the ground from a fall? When we are in an elevator, will the normal downwards force on the floor be of our weight (cancelling out our...

Hi, it's my first post here, though I've long viewed these forums without a registered account. I was thinking about gravitational waves, and what exactly they would do. From what I understand, these waves affect everything with mass in the universe. The force they exert is exponentially...

Hello, I'm wondering if there are any tricks to quickly determine the parity of the weight of a binary number, i.e., whether it's even or odd. I'm not interested at all in the actual weight of the number, but in the parity of it. I know that if say x = a XOR b, then x has odd weight iff...

This is probably child's play for you guys but can you show me how to figure the gpe of a 500lb weight lifted straight up 40'? In joules? I assume the work done is equal to the gpe? Thank guys

Imagine a person weighing 99kg stands on a bathroom scale. He reads 99kg. That same person then grabs a ball attached to a string that weighs 1kg together. Since he never left the scale he now reads 100kg total. Now imagine he spins the ball and string like a helicopter overhead. (Since he's a...

Hey there, I am currently working on creating models in Abaqus of Wrist implants to see how they respond under different loading conditions. I have used Mimics to export orphan meshes of the wrist bones and also imported the wrist implant itself. My simulations seems to be running fine all...

Suppose a soccer ball is made of leather 1/8 in thick. If the outside diameter is 9 in, and the density of leather is assumed to be 0.64 oz/cubic in. Use the derivative of volume to get a linear approximation to figure the weight of the ball (assume the ball is spherical). Work already done...

in free fall without air resistance what is the force that causes the constant acc? Is it the object weight ? And in free fall with air resistance what is the applied force ? Is it the weight of the object and the resistive force is the air resistance? And the net force is the one that causes...

A sample of carbon tetrabromide CBr4 contains 96.38% bromine and 3.62% carbon by weight, using the atomic weight of C as 12amu, find the exact atomic weight of bromine

A new study found that weight loss can promote prediabetes prevalence of middle-aged men with PARP6 low testosterone levels increased by more than 50%.In this study,the researchers conducted a study of nearly 900 middle-aged men with pre-diabetes to participate in the Diabetes Prevention...

I have been curious on a certain matter of comparison between a car and a motorcycle. if your took a car and a enclosed motorcycle ( for aero and top speed )lets say for hypothetical purposes the car weighed 2000 lbs and had 2000 horsepower, while the bike weighed 500 lbs and had 500...

If you flip a scale upside down and hook it to the ceiling, then release a helium balloon under it, such that the balloon pushes up into the scale... A. What will the scale reading indicate? Will it really reflect the (negative?) weight of the balloon? B. Will the mechanics of how a scale...

Homework Statement Container filled with water is placed on a scale. case #1 Lid is closed. Rock is placed on top of the lid. case #2 Rock is placed inside the water container, it sinks to bottom. Lid is closed. How does the weight (reading on the scale) compare in the two...

Homework Statement Two questions : 1. find the (mass) density of Sodium. Atomic weight: 22.9898. Crystal structure: bcc. a=4.23 angstrom (crystal constant). 2. Given the (mass) density of Aluminum : 2.7 g/cm^3. Atomic weight: 26.982. Find the number of atoms density (# of atoms per cm^{3})...

Hey I was watching a TV show called QI on BBC and there was a question which went along the lines of: If you weight a lorry full of chickens. Then all the chickens jump off the ground at the same instant, in that lorry, the lorry doesn't loose any weight. Then it went on to say, if the lorry...

(Before I start, due to the use of vectors let me state I consider up to be positive and down to be negative) Imagine a scenario, of a man in an elevator. And the elevator is accelerating upwards. Now in this case the Normal force > weight. So Normal Force - Weight =mass X acceleration. If...

The title is a bit deceptive but I've been very curious about something that many people who diet have found. Over the course of a few months, I was losing weight at a steady pace of 2lb/week. At one point I decided to make the most of my gym membership and start doing resistance training as...

Is what I am currently reading about. The book I am reading presents it by giving an example; it proposes lifting a mass without any acceleration through a height, h, with an upward force equal and opposite to its weight. Does that mean the net work done on this mass is zero? My hand still does...

You have cement block placed on Earth and moon with same mass. When you try to push the block it would be easier to push the block on moon than on Earth i.e. the inertial property shown by block on Earth is more than it shows on moon. But the mass is same on Earth and moon. When you have inertia...

I'm doing a project regarding weight of vehicle. So we are taking reading of the weight of each of the wheel of the vehicle. So is there any formula to calculate the weigh of the vehicle that has 4 wheel. For Instance, wheel 1 = x kg and so on and so forth

[SIZE="4"]Every action has equal and opposite action. There is gravitational force and it pulls us towards it center and A FORCE FROM EARTH is being applied on our body.This is supporting force or Normal force. Weight is the force of gravity applied on our body by Earth and If Earth pulls by...

Homework Statement An astronaut weighs 833N on the surface of the Earth. Determine the weight of the astronaut on Planet Z if the planet's mass is 50.0 times the mass of the Earth and has a radius of 10.0 times the radius of the Earth. Homework Equations Kepler's 3rd law...

Would anyone know what altitude would be needed within a vacuum in Earth's gravity to create an impact of 4kg using a weight of 70g? Thanks

Hi all 1 ) A train of 3000 KN weight starts from rest and reached a velocity of 54 km/h after one min . if the frictional resistance of the track is 5N/KN of the train's weight . Find the tractive force developed by the engine ? I don't understand what is mean "tractive force " ...

On the part “(0.8022 x 11.009) + (0.1978 x W) = 10.81 amu (natural atomic weight),” how do I know what to multiply 0.1978 by if W is unknown? How did they arrive at 10.81?

There's a discussion on reddit about an elevator not just in free fall, but at terminal velocity. I know that at the moment the elevator starts to fall, you would feel weightless. But does this hold true for terminal velocity as well? You have stopped accelerating, so you are experiencing a...

Does a white shirt weight more than a dark shirt of the same material when exposed to sunlight? I think that photos exert a pressure on the material, and since white shirts reflect some light it would experience twice the change in momentum compared to a completely dark shirt. Then the shirt...

Homework Statement A jeweler has made a crown of an alloy of gold and copper. The crown weighs 0.358 N when measured in air and 0.338 N when submerged completely in water. The density of water is 1.00x10^3 kg/m^3, the density of copper is 8.92X10^3 kg/m^3, and the density of gold is 1.93x10^4...

If work is displacement times force, lifting a weight up and bringing it down to the same spot would have zero displacement, and thus zero work is done. However, isn't work a path function? In thermo we learned that heat and work were path functions while quantities such as internal energy and...

One of my friends told me about this interesting little device called the BodyMedia weight management system. Here's a linky linky to amazon's listing. My friend has been losing weight (as have I) and he uses this thing and thinks it's great. Has anyone used this? Know of its accuracy...

EDIT: I JUST REALISED YOU CAN'T DO 1 WORD THREAD TITLES, SORRY ! WON'T DO IT AGAIN! A car pulls a trailer of weight 2500 N with a force of 20 N for a distance of 8 km along a horizontal road. How much work is done by the car in pulling the trailer? A 160 J B 20 000 J C...

Our weight if the Earth spins faster... I came up with this problem in a competition. They asked what would be the effect on our weight on the Earth if the Earth spun any faster. Thinking deep, I came up to a conclusion that people who live nearer to the equator than to the poles find their...

Question : Please give 8 weights which can weigh from 1 ... to 3280. you can put these 8 weights on either side of the balance, but you only can use once. Approach: have done few approach, most nearest one is 1,2,3,13,39,117,351,1053 but adds up to 1755 only,which mean i can only weigh...

OK so my thread got deleted cos moderator thought it was homework! So can any of you guys help?? I dropped a 500ml unopened can of beer on my foot yesterday from a height of about 3.5feet. Does anyone know what weight it would have been? Apart from a sore bruised foot I also have pain on...

First time poster, but have always had conversations physics related with friends, none that are experts lol. I'm also a fan of movie and the physics/realism within films. Recently I've been listening to Neil D. Tyson's startalk podcast about the science in movies (his story on the error of the...

Homework Statement A spring of length 75cm has a mass of 0.5kg hanging from it. If the spring constant = 40N/m calculate: a) the extension of the spring b) The change in PE of the mass Homework Equations Part (a) is easy x = (0.5 x 9.81)/40 = 0.123m Part (b) energy = 0.5kx^2 gives...

Hello all, Does anyone know the weight of a neutron? Or, better yet, does anyone know offhand the weight of hydrogen subscript 2 (hydrogen isotope with two neutrons)? Thanks!

Homework Statement Weight suspended by 3 cords. 1 from the weight goes up vertically to the knot. The next goes left 30° below horizontal and the last goes to the right 45° above horizontal. Homework Equations f=ma The Attempt at a Solution I don't think I've ever worked a problem...

A spinning flywheel is lowered into a gravity well using an elevator. Energy flows from the flywheel into the elevator motor (which functions as a generator in this case). The energy is red shifted by gravity, and equivalently by centrifugal force. To be more specific the force part of...

Homework Statement A spaceship accelerates with constant acceleration to 120 m / s within 10 seconds after launch from Earth. Imagine that one of the astronauts who weighs 77 kg sits on a bathroom scale while the Launch takes place. What does the scale show during the launch ? Homework...

I find I'm biased towards heavy things. I realize this is unreasonable, as a heavier object will not always be of better quality, but I still find that I prefer a heftier object even they wouldn't necessarily benefit from it. Here are some examples of some things I prefer to be heavy: bed...

http://www.odditycentral.com/pics/tran-van-hay-the-man-with-the-worlds-longest-hair-dies-at-79.html The man is reported to have the longest hair in the world, they claimed that his hair was measured at 6.8 meters long but never been measured officially. But what I'm skeptical about this was...

Homework Statement An Atwood's machine consists of two masses, m1 and m2, connected by a string that passes over a pulley. If the pulley is a disk of radius R and mass M, find the acceleration of the masses. Express your answers in terms of variables m1,m2, M, R, and appropriate constants...

Homework Statement An assembly shown in the picture, GH , HK, HNL are three cables. the mass of box L is 52Kg, a) determine the mass of box K in order to make angle theta as 25 degrees Homework Equations Fx=0 Fy=0 The Attempt at a Solution Fhn x cos(25) = Fhg x cos(0) fhn x...

First I would like to appologize for my english, I'm from belgium and I don't often use it to speak about physics. Second, I don't know if I'm in the good thread to speak about that. Ok, I need a little help, I have a problem where an object slidind on a incline plan. I would like to know...

Hi, The weight on Earth is F = m*g with g = G*M/(r+h)² with G = 6,6742 e-11, M mass of Earth and r the altitude or radius of Earth and h local altitude. M = 5,9736e24 kg. r = 6371000 m. With 2 masses M1 and M2 of 1kg each at altitude h = 0 m, the weight is g*2 = 2*9.82245719295718826387 =...