Work Definition and 998 Threads

Homework Statement A sled is pulled across the barren winter landscape at an angle of 26.0° from the ground with a force of 74 N. If the sled is pulled over a distance of 27 m, how much work was done on the sled? Round your answer to two decimals Homework Equations W = f x s x Cos The...

Greg Bernhardt submitted a new PF Insights post Make Units Work for You Continue reading the Original PF Insights Post.

Homework Statement 14.6 The coefficient of kinetic friction between the slider and the rod is μ, and the free length of the spring is ##L_0 = b##. Derive the expression for the work done by the friction force on the slider as it moves from A to B. Neglect the weight of the slider. Homework...

Homework Statement Derive the expression for the work done by the ideal spring on the slider when the slider moves from A to B. Assume that the free length of the spring is (a) ##L_0 = b##; and (b) ##L_0 = 0.75b## Homework EquationsThe Attempt at a Solution Can you check if my solution...

Homework Statement The work done W by an expanding gas is calculated using W = pΔV. What must remain constant for this equation to be used? a. The pressure of the expanding gas b. The pressure of the surroundings c. The temperature of the expanding gas d. The temperature of the surroundings e...

Hi, I have a homework and I kind of stuck on it. Here is the question: A 17 kg object on a rough ramp (coefficient of friction = 0.35N, ramp's angle = 25 degrees) is connected to a vertically hanging object via a pulley with I = 23 kg m^2 and the radius is 0.25m. The hanging object had weight...

Homework Statement The question is as follows: A 50kg ice skater is gliding along the ice, heading due north at 4.0m/s. The ice has a small coefficient of static friction, to prevent the skater from slipping sideways, but kinetic friction =0. Suddenly, a wind from the northeast exerts a force...

Homework Statement A force applied to a tennis ball is described by the function F(x) = 2x + 5, with the force in Newtons and the position in meters. How much work does the force do on a tennis ball as it moves from -2.5 m to a new position of 2.4 m? Homework Equations F(x)= 2x+5 force x...

I'm a mother of young children with a bachelor's in Physics and a master's in Electrical Engineering. I can't work full-time and commute right now, so I want to take some courses to position myself to get into an industry that would allow me to work from home most of the week. Other than...

Homework Statement g = ##10m/s^2## ##\sqrt{3}## = 1.7 Determine work by the 20N force Homework Equations for an inclined plane: W = ((F+mgsin30)-(mgcos30)μ)s -> (Fx-ff)*s for object pulled with angle: W= (Fcos60-(mg-Fsin60)μ)s -> (Fx-ff)*sThe Attempt at a Solution W=...

Homework Statement The temperature of a 12-oz (0.354-L) can of soft drink is reduced from 20 to 5 ºC by a refrigeration cycle. The cycle receives energy by heat transfer from the soft drink and discharges energy by heat transfer at 20 ºC to the surroundings. There are no other heat transfers...

Homework Statement A factory has gotten an order for ##N## products. For this job it has ##n## available machines.If all the machines would work simultaneously the order would have been completed in 24 hours. However due some complications there exist only two possible way to build the...

Homework Statement as title Homework Equations force exerted by atmosphere on bubble = 2(on account of dual layer) * 2pi*r*L(surface tension) work is the integral of force *dx The Attempt at a Solution so we're looking at int ( 4pi*r*L *dr) but since not it 1 particle is traveling against...

Homework Statement A standard man climbs 15 m up a vertical rope. How much energy (in cal) is dissipated as heat in a single climb if 23% of the total energy required is used to do the work? (Assume the standard man has a mass of 70 kg.) Homework Equations Q = mgΔh The Attempt at a Solution I...

I am confused how a charge could have negative work done. To clarify, I was doing a problem earlier in which a positive charge and negative charge are moving towards each other. I used the equation work = Δv * q And when I was doing this, the change in electric potential, Δv, was negative, and...

Please see attached sketch. I am trying to determine the total work done by this system. I am not sire where to even start. I know w=fd, but i am not certain how that applies to a rotating object. Please advise.

If an object with 1kg mass falls free (no air drag), from 100 meters high, and the gravitational acceleration is 9.81, then the mechanical energy will be: 1*9.81*100 = 981 joules. The work the gravitational force does on the object will be: 9.81N*100m = 981 joules. Another object with same...

Assume a person is at space, and assume there's no friction or gravitational force in that space. The person has a bow and arrow. He stretches the arrow on the bow, and then shots the arrow out in the space. Since there are no friction and gravitational force in that space, the arrow will have...

Homework Statement A sample of 1.60 mol H2 (Cv = 20.5 J K-1 mol-1) at 21°C and 1.50 atm undergoes a reversible adiabatic compression until the final pressure is 4.50 atm. Calculate the final volume of the gas sample and the work associated with this process. Assume that the gas behaves ideally...

When we calculate the work done by a force applied on an object (suppose force and movement are in the same direction and a constant force) do we take into account the relative distance ot the absolute distance. When saying relative distance i mean if the object is moving on top of a platform...

Here is problem I quickly made up: Suppose there is a ramp with a height of 6 meters and length of 12 meters. A block of 5 kg is pushed up to the top of the ramp with a constant velocity. The force of friction is 15 N. Here's the confusion: By using the non-conservative force work energy...

Homework Statement How much work per step per leg in the race? How much work must he (single leg) squat to equate 1 step of work in the race? The given variables are: Displacement: 100 meters Time: 9.65 seconds runners weight in kg= ? 100 steps to complete 100m race, alternating legs...

Homework Statement [/B] In gravity-free interstellar space, a spaceship fires its engines to speed up. The total thrust of the engines as a function of position is shown in the graph below. F on the graph represents 79 kN of thrust. The rocket's mass is 11500 kg. Note the units on the graph -...

Homework Statement [/B] A force acts on an object along an x axis. The force varies with position as shown in the graph below. On the graph, F = 52.0 N. Find the work done by the force as it moves the object from x = 0 to x = 15.0 m. Homework Equations [/B]The Attempt at a Solution So what...

Homework Statement I need to solve the following D.E for ##\phi(x,t)## $$[\frac{\partial}{\partial t} - D \frac{\partial ^2}{\partial x^2}]\phi (x,t) = f(x,t)$$ with the help of the following DE with a Green's function $$[\frac{\partial}{\partial t} - D \frac{\partial ^2}{\partial x^2}]G...

Homework Statement Let ##G## be a non-directed graph with non negative weights. Prove that the multiplicity of the eigenvalue ##0## of ##L_s## is the same as the number of convex components ##A_1,\dots, A_k## of the graph. And the subspace associated to the eigenvalue ##0## is generated by the...

Homework Statement A grocery cart with mass of 19.3 kg is pushed at constant speed along an aisle by a shopper who exerts a force of 13.1 N on the cart at an angle of 18.3 from the horizontal. The aisle is 15.1 m long. The coefficient of friction is 0.0658. Find the work done on the cart by...

Hello, I want to make a Slayer Exciter circuit with a Tesla Coil. I have my parts laid out, but I want to make sure that they would work before purchasing them. Off and On switch I have one 0.5'' PVC pipe I assume any would work 9v Battery I own one 9v Battery holder I own one 22k ohms...

Hi guys. I want to make a question about what kind of job can a physicist do. Excluding the academic carrier and the research, which kind of job can a physicist do? It is true that there are physicist that work at Wall Street? If yes, what kind of job they do there? A technical job? I don't...

Homework Statement A spiral staircase in a building is in the shape of a helix of radius 5 meters. Between two floors of the building, the stairs make one full revolution and climb by 4 meters. A person carries a bag of grocers up two floors. The combined mass of the persona and groceries is 70...

Too many on the market, too many promises. Is there certain chemicals that I should look for when I'm shopping for pet odor removal products? Move okay. (Chemistry? General?)

Homework Statement Homework Equations W = ΔKE W = KEf-KEi The Attempt at a Solution W = .5mvf2 -.5mvi2 I know that final KE for A is 4 times the KE of B because for A ... KEf = 1/2 m (2v)^2 4KE = 1/2 m v ^2 for A I don't know what initial KE for both of them are... so how do i know if that...

Hello, Consider two equal masses moving away from each other at the same speed. The total momentum of the system is zero, so the total momentum of the system is zero. Therefore, the centre of mass has no speed. The total energy in the system is ##mv^2##, due to the kinetic energy of the two...

These two things seem to be exactly the same (even down to the same formula), so I'm having difficulty understanding why they are two different terms. Is circulation just the work done as you go around a circle once?

Homework Statement Estimate the pressure increase required to impart 1 J of mechanical work in reversibly compressing 1 mol of silver at room temperature. What pressure rise would be required to impart 1 J of work to 1 mol of alumina at room temperature? For alumina take the molar volume to be...

Homework Statement Calculate q, w, ∆E, and ∆H for the process in which 93.0 g of nitrous oxide gas (N2O) is cooled from 179°C to 55°C at a constant pressure of 4.00 atm. Cp(N2O) = 38.70 J K-1 mol-1 Homework Equations q= mCΔT ΔH=n(Cp)=n(qv)ΔT ΔE=q+w w= -pΔV *Probably something else too but I'm...

Homework Statement What is the minimum work needed to push a 1000-kg car 300 m up a 17.5 degree incline? A. Ignore friction B. Assume the coefficient of friction is 0.25 Homework Equations W = F*d Net force = ma The Attempt at a Solution At first I did: Work = F*300*cos17.6 but I later...

Greetings all, I am an undergrad working on my first first-author paper in theoretical / computational condensed matter physics (near the computational materials science end of the spectrum) and I am looking to getting it published. My advisor has published in many journals, from mid to high...

I have the problem below. I know that net work is equal to the change in kinetic energy which is Wnet= 0.5mv^2-0.5mvi^2.I also know that the work by force of gravity is the same for both objects. I don't understand why the objects would be the same speed at the finish line.

Homework Statement Kerry is pulling a 156-kg sled along a snowy, horizontal path with a 620-N force directed at an angle of 29.0° above the ground. He pulls the sled over a distance of 26.0 m, and the coefficient of kinetic friction between the sled and the ground is 0.0622. I need to find the...

The question that puzzled me during lecture! : A block is pushed so that it moves distance L up a ramp (incline angle q ) at constant speed. If there is friction, the magnitude of the work done on the block by friction…(ramp is up and leftwards) A. is mgsinqL. B. is less...

Homework Statement This is a lab I did for physics. In this experiment, a glider starting from rest on an air track is attached to a string. The string is drawn over a pulley with a mass hanger tied to the other end. Work is done by gravity which results in a gain of kinetic energy of the...

Homework Statement In the question, a person is pulling a 156 kg sled up a hill. A 620 N force is used to pull the sled up the hill that has an angle of 29° with the horizontal. The sled is pulled a distance of 26 m, and the kinetic friction coefficient is 0.0622. The system has been defined as...

For a conventional wings, at high speed or fast roll, the leading edge of the wings will bend downwards. This will decrease angle of attack and subsequently lift. How does AAW make the wings bend the other way round? Is it due to the materials or the shape of the wings that is designed? If such...

https://www.sciencedaily.com/releases/2017/10/171027085523.htmCurrent federal efforts to revive the coal industry will likely do more harm than good to fragile Appalachian communities transitioning from coal as a major source of employment, according to a new study. What do you think...

Homework Statement The speed of the pendulum bob remains constant as it travels around the circle (a) Over one complete circle, how much work does the tension force F do on the bob? (i) A positive amount; (ii) a negative amount; (iii) zero. (b) Over one complete circle, how much work does...

Here is a screenshot of the question I deleted on stack physics after they directed me to this forum. Eratta: FYI I have tried with g = -9.80 and 58.9 m when the correct solution (I think) is 5.9 rounded two significant figures. Thanks for any help!

Hello first time posting anything like this to people that have a better grasp on these ideas. Please pardon the lack of proper language structure. So to my understanding that light travels on photons. The light from a source comes out in waves and particles. As it travels redshift will happen...

Homework Statement x1= -2, x2= 2 F1= 1, F2= -2 Graph in uploaded image Homework Equations w= F* del x* cos(theta) The Attempt at a Solution I am trying to find the area under the points of F and x but it has an irregular shape and i don't know what to do? Should i do w= (f1-f2)(del x)?[/B]

Homework Statement [/B] F =< 2x, e^y + z cos y,sin y > (a) Find the work done by the force in moving a particle from P(1, 0, 1) to Q(1, 2, −3) along a straight path. (b) Find the work done by the force in moving a particle from P(1, 0, 1) to Q(1, 2, −3) along the curved path given by C : r(t)...