Work done Definition and 1000 Threads

Homework Statement Find the work done by the force field F in moving an object from P to Q. F(x,y,z)=10y^(3/2)i+15x\sqrt{y}j P(1,1), Q(2,9)Homework Equations W = \intF dot drThe Attempt at a Solution I have no clue how to do it

Figure 20-29 shows a reversible cycle through which 1.00 mol of a monatomic ideal gas is taken. Assume that p = 2p0, V = 2V0, p0 = 1.13*10^5 Pa, and V0 = 0.0235 m^3. Fig. 20-29 http://s1142.photobucket.com/albums/n603/bdoneski/?action=view&current=hrw7_20-29.gif" (a) Calculate the work done...

Homework Statement 1 mole of an ideal gas is at 9 atm pressure, occupies 1 L and has an internal energy of 474 J. The gas is first cooled at constant volume until its pressure is 1 atm. It is then allowed to expand at constant pressure until its volume is 7 L with an internal energy of 766...

Hi guys, :smile: Work Done = Force x Distance x cos of Theta - the angle between the Force and the Displacement Vector / direction of motion In Circular motion I know the force but I am given velocity. In order to prove that no work is done is it correct to say the following: If we have two...

Hi :smile: So, let's go straight to the point: a = v - u / t Kinetic Energy: 1/2 mv2 Ok, I understand that a acceleration, a change in velocity, will change the Kinetic Energy since v is part of the Kinetic energy equation. But acceleration is not simply a change in velocity. It is the rate...

Homework Statement An ideal gas follows the three-part process shown in the figure. At the completion of one full cycle, find the net work done by the system. Homework Equations W=P*deltaV; Total Work = Wab+Wbc+Wca A=1/2bh The Attempt at a Solution Work done from C to A is zero, because...

Homework Statement http://img26.imageshack.us/i/1113001.jpg/ #11 Homework Equations C = 2πr w=fd The Attempt at a Solution it travels from point 1 to 2 so its half a circle so the distance is πR. πRF = w so i would guess its D. but the answer is A) zero. i do not know why...

Homework Statement When a volume 10^-3 m^3 of a certain gas at a pressure of 1 atm undergoes a reversible adiabatic compression to half its volume, its pressure rises by a factor of three. The internal energy of the gas is given by E=3PV, where P is the pressure and V is the volume. By making...

Homework Statement The pulley in the illustration is a uniform disk of mass 2.40 kg and radius 0.220 m. The block applies a constant torque to the pulley, which is free to rotate without friction, resulting in an angular acceleration of magnitude 0.180 rad/s2 for the pulley. As the block falls...

Homework Statement In a cylindrical region of radius R, there exists a time varying magnetic field B such that dB/dt=k(>0) . A charged particle having charge q is placed at the point P at a distance d (> R) from its centre O. Now, the particle is moved in the direction perpendicular to OP (see...

Homework Statement How much work is done by a force= (2x)i N + (3)j N with x in meters, that moves a particle from a position (initial) = (2m)i + (3m)j to a position (final) = (-4m)i + (-3m)j? Answer: - 6 J Homework Equations Work = integral of Force The Attempt at a Solution...

Homework Statement A 230 kg crate hangs from the end of a rope of length L = 12.0 m. You push horizontally on the crate with a varying force to move it distance d = 4.00 m to the side (Fig. 7-43). (a) What is the magnitude of when the crate is in this final position? Figure...

Homework Statement A coin slides over a frictionless plane and across an xy coordinate system from the origin to a point with xy coordinates (2.2 m, 6.1 m) while a constant force acts on it. The force has magnitude 8.2 N and is directed at a counterclockwise angle of 108° from the positive...

Homework Statement A tank of water is 3m long and has a triangular cross section of height 1m and width at the top of 1m. How much work is done pumping the water to the top of the tank? The density of water is 1000kg/m3 and the gravitational constant g has value g m/s2 Homework Equations...

An electric elevator with a motor at the top has a cable weight 4.5 lb/ft. When the car is at the first floor, 198 ft of cable are paid out, and effectively 0 ft are out when the car is at the top floor. How much work does the motor do just lifting the cable when it takes the car from the first...

Hello, Was wondering if anybody could help with the following question as I am struggling, and this area is not my strong point. Note this is not homework purely self-study, out of curiosity to help me understand the subject area in more detail. In each minute a pump draws 2.4m^3 of water...

Homework Statement How much work is done against gravity to fire a 7.2*10^2 kg weather monitor 120km into the air. Homework Equations Mass Earth = 5.98*10^24kg radius of Earth = 6.38 * 10^6 m Eg = -GMm/r delta Eg = Eg 2 - Eg 1 The Attempt at a Solution Eg1= -[(6.67*10^...

Homework Statement Imagine a block with mass m being pulled up a frictionless incline with upward angle theta by a rope with tension force T. The mass is pulled until another point of rest at a point distance d away from the original point (with d measured on the incline) and h measured on the...

Homework Statement There's a cone with height 12 feet and radius 4 feet. It is filled with water to a depth of 9 feet. Find the work required to pump the water over the top. The density of water is 62.4lbs/ft^3 work=force*distance & force=volume*density The Attempt at a Solution...

Homework Statement a cyclist rides up a steady slope for a distance of 1200m and rises 90m vertically as a result. the total mass of rider + cycle is 80kg a) assume a drag force of 10N opposing the motion(due to air resistance and friction), what Total Work must be output by the rider for...

Homework Statement In the temperature range 310K and 330K the pressure of a non ideal gas is related to volume V and temperature T by P=(24.9 J/K) T/V− (0.00662 J/K^2)T^2/V. How much work is done by the gas if it's temperature is raised from 310K to 320K whilst pressure held constant...

Homework Statement A block of mass 1.60 kg is pulled up a rough 30 degree incline at constant speed by a string parallel to the surface. The friction force on the block is 7.00 N. The incline is 4.00 m long and 2.00 m high. (1) How much gravitational potential energy did the block gain...

Homework Statement A block is being slid along a rough surface by a force of 94.6 N forming an upward angle with the horizontal of 29 degrees. The mass of the block is 18.7 kg. It is displaced 70.6 m, and the coefficient of friction is .186 what is the total work done by the force...

Our local YMCA is putting on an indoor triathlon and I am trying to come up with a formula to help them determine the winner of the cycle segment. The indoor triathlon consists of a 10 minute pool swim, a 20 minute cycle on an indoor, stationary bike, and a 20 minute run on the treadmill. The...

Homework Statement Two blocks are connected by a very light string passing over a massless and frictionless pulley (Figure ). The 20.0-N block moves 75.0cm to the right and the 12.0-N block moves 75.0cm downward. Find the total work done on 20.0-N block if there is no friction between the...

Hi, In deriving the equation for adiabats : V^{\gamma}P = C. It is assumed that the work done during the process is W = -P \Delta V. But calculating the work done from V^{\gamma}P = C we obtain: W = \frac{C}{1-\gamma}\left[ V^{1-\gamma}_{f} - V^{1-\gamma}_{i} \right] . Also, i believe to...

Homework Statement A 0.245 kg ball is thrown straight up from 2.20 m above the ground. Its initial vertical speed is 12.40 m/s. A short time later, it hits the ground. Calculate the total work done by the force of gravity during that time. Homework Equations 1/2m(v initial)2 + mg(h...

Homework Statement The floor of a basement in a house is 3.2m blow the grade of a window sill. If the Basement has flooded to a depth of 0.44m and the basement is 10.3m by 18.4m. If the water leaves the pipe at 2.4m/s, how much work was done by the pump. (Density of water is 1000 kg/m^3)...

Homework Statement A box, whose weight is 182 kg, is drawn with constant speed 21 m along a horizontal concrete floor. The kinetic friction between the box and the floor is 0.58. (acceleration due to gravity, g = 9,81 m/s2). Homework Equations Calculate the work done when the box is drawn...

I am having a little trouble understanding this and I was wondering if I could get some help. I understand that work done at constant volume is zero because since the volume isn't changing, there is no movement on the boundaries and therefore no work. But it isn't coming out mathematically...

Homework Statement A 12 kg brick moves along an x axis. Its acceleration as a function of its position is shown in Fig. 7-37. What is the net work performed on the brick by the force causing the acceleration as the brick moves from x = 0 to x = 5.2 m...

1. Homework Statement [/b] A block of weight mg sits on an inclined plane as shown. A force of magnitude F is applied to pull the block up the incline at constant speed. The coefficient of kinetic friction between the plane and the block is Mu. What is the total work done on the block by the...

Hello, I have a question that should be pretty simple, but I can struggling to understand: What determines the amount of work done in lifting a ball from one to two metres above the ground? I know that W=Fd and F=ma , so I would assume that the work done would equal m*a*d. Something...

A force acts on a particle of 1.6kg mass, the force is related to the position of the particle by F=0.5x^{3} Find the work done by the force as the particle moves from x=3.8 m to x=2.0 m. By plugging each value of x into the force equation I get that: F at 3.8 m = 27.436 N F at 2.0 m =...

The problem states: how much work is done in moving an electron from a distance of 1nm to a distance of 10nm away from a hydrogen nucleus? My attempt at the problem is using the W=\DeltaU=q\DeltaV. With this equation I would get a positive work. However, when I reason through the question, I...

Homework Statement A paddle turns at 28.0 rad/s and exerts a torque of 16.0 Nm to stir the paint. Internal energy increase of 12.5kJ causes the temperature of the paint to increase by 1.00K. If there where no heat flow between the paint and the surroundings, what is the change in temperature...

Homework Statement A box is dragged 16 m across a level floor by a 75N force at an angle of 35 degrees to the floor . It is then dragged by the same force 8m up a ramp inclined at an angle of 20 degrees to the floor. Determine the total work done by the force. Homework Equations W= F(d)Cosθ...

Hello, I'm trying to figure out a method of calculating the work done by friction on an object sliding down a surface with a variable slope, assuming an equation can be determined to fit the line along which the object travels and we have a known coefficient of friction for the surface...

Homework Statement A cable weighing 2 pounds per foot of length (and so having a mass of 2 pounds per foot) is suspended from the top of a well 200 feet deep and extends to the bottom. Find the work done in raising the cable to the surface. Over the distance of 200 feet you may use 32m as the...

I read in my book that when we are calculating the amount of work done by a man to go up a flight of stairs we use as force his weight and the distance, the vertical displacement. Then, looking at this website http://www.physicsclassroom.com/mmedia/energy/au.cfm they illustrate a car going...

Homework Statement A sample of dry air has initial pressure p1 = 1000 hPa and temperature T1 = 300k. It undergoes a process that takes it to a new pressure p2 = 500 hPa with unchanged temperature T2 = T1. Compute the mechanical work per unit mass performed by the sample under the following...

Homework Statement Find the work done by a force of 3 Newtons acting in the direction 2i + j + 2k in moving an object 2 meters from (0, 0, 0) to (0, 2, 0). Homework Equations Commonly known vector operations. The Attempt at a Solution I found the displacement vector to be 2j...

Homework Statement Let a wire's tension increase quasi-statically from F_{1}\rightarrowF_{2}, with Young's Modulus Y, Cross-sectional Area A, and Length L. Find the work done Homework Equations F=\frac{YA}{L} *Delta L, tex having issues W= Integral from L to L_2 The Attempt at a...

Homework Statement Find the work done to move a test charge with charge q from the origin to the edge of a spherical conducting shell which surrounds it, also of charge q. (Shell is of radius R). Homework Equations W = int(F.ds) where W = work done, F = force The Attempt at...

Homework Statement A chemical reaction takes place in a container of cross-sectional area 100 cm2. The container has a loosely fitting piston at one end. As a result of the reaction, then piston is pushed out by 10 cm against an external pressure of 101.3 kPa. Calculate the work of expansion...

Homework Statement A man of weight W is in an elevator. The elevator accelerates vertically up at a rate a and at a certain instant has a speed V. The man then climbs a vertical ladder within the elevator at a speed v relative to the elevator. What is the man's rate of expenditure of energy...

Hi there! I'd like to calculate the work done by the gravitational force. I know the work is defined by the integration of a 1-form: L=\int_\gamma \omega where \omega=F_xdx+F_ydy+F_zdz This works fine in cartesian coordinates and I know how to integrate it, but what if I want to use spherical...

Homework Statement A mass of 5kg of saturated water vapor at 300kPa is heated at constant pressure until the temperature reaches 200*C. Calculate the work done by the steam during this process. Homework Equations The Attempt at a Solution

this isn't homework, I am doing revision for an exam :) a 180 microfarad capacitor is charged so that is has a PD of 100v across the plates. i calculate the energy stored as 0.5cv² = 0.9J the question then asks me to calculate the work done by the battery in charging the capacitor. the mark...

Homework Statement Two pounds of air contained in a cylinder expand without friction against a piston. The pressure on the back side of the piston is constant at 200 psia. The air initially occupies a volume of 0.5 ft3. What is the work done by the air in ft-lbf if the expansion continues until...