Work done Definition and 1000 Threads

Homework Statement Homework Equations no The Attempt at a Solution [/B] I assumed the path from c to a to be a straight line and I'm unable to find the work as the area in the image above. (sorry my poor english). The book's answer is -2460 J. The answer I found is ≅ -1112 J. My...

Homework Statement A metallic sphere is placed inside a hollow spherical shell. The potential on the inner and outer spheres is 10 V and 5 V respectively. What is the potential at the center?(The spheres are concentric.) Homework Equations $$V =\frac{kq}{r}$$ The Attempt at a Solution The...

Homework Statement Homework Equations no The Attempt at a Solution no Since the problem asks how much work was done by OR on the gas, I did not understand why the book's answer is 162 J instead ±81 J that I've found. (sorry my bad english) Sorry, the correct question on the problem is how...

What is the difference between work done by a force and work done against a force?How would we calculate the two and what is the mathematical relation between the two. Please help. Thanks.

~In the vacuum of outer space~ If a rocket motor exerts a force of 1 Newton on a mass of 2 kilograms for 1.414213562 seconds over a distance of 1 meter, how many Joules of work have been done? I thought Work = 1 N x 1 m = 1 kg 1m2 1s-2 = 1 J so Work = 1 N x 1 m = 2 kg 1m2 1.414s-2 = 1 J ? I...

Homework Statement Hello, I just need help figuring out how to calculate the work done by the gas molecules for my physics homework :) Formula given: W=Px∆V (W=work, P=pressure, and V=volume) What I know: So my calculated volume is 1.7x10^-22m^3. Pressure=0.25 A t m (atmospheric pressure) I...

Homework Statement Hello. I am having trouble understanding this particular statement found in one of my textbooks. " Work done to move a charge along a line perpendicular to the field is zero" The Attempt at a Solution Field is a space around a charge where if we place any other charge...

I have seen this calculation on web Let consider that old man displaced the cart from pole A to Pole B on platform. Observers are on platform S & in train S', moving with velocity –V then (let, X-axis is parallel to train direction) 1) When AB (displacement) parallel to the direction of train...

Homework Statement Water is pumped steadily out of a flooded basement at 5.0 m/s through a hose of radius 1.0 cm, passing through a window 3.0 m above the waterline.What is the pump’s power? Homework Equations Volume and mass flow rates are constant R_v = Av; \quad M_v = \rho A v...

Say I take a brick and push it and it moves, so work is done and chemical energy in my body is transferred into kinetic energy of the brick, which is then transformed to heat energy due to friction, so I have to keep pushing to transfer more of my chemical energy into kinetic energy of the...

Homework Statement Two cylinders of base area 4cm2 hold fluid of density 1.30(103). In one the fluid has height .854 and the other has height 1.560. They are then joined and the fluids equalize in height--find the work done by gravity on the fluid. Homework Equations A version of...

Homework Statement I was just wondering whether the following notes I took on work in physics are accurate? Or have I got my understanding wrong? Note on friction Following from the example of the dragging object above… The object stops because it loses kinetic energy due to friction. How...

Homework Statement A conduction rod (of mass ##m## and length ##l##) was placed on two smooth conducting rails rails connected by a resistor as shown: (the circuit is placed in ##XY##-plane A constant uniform magnetic field is switched on along ##-Z## direction with magnitude ##B## The rod is...

Homework Statement A 1.00 mol sample of an ideal diatomic gas at a pressure of 1.00 atm and temperature of 420 K undergoes a process in which its pressure increases linearly with temperature. The final temperature and pressure are 720 K and 1.60 atm. Determine the work done by this gas during...

Hi everybody, I now encounter some problems when try to solve this: Problem statement: Calculate the work done to blow a soap bubble to radius R. Knowing that the process is isotherm, the atmospheric pressure is H, the surface tension is γ. Solution: $$A = A_{1}+A_{2}$$ In which A1 is the work...

Homework Statement A box was dragged downward from the state of rest through an inclination 10.0 m at an angle of 25 degree. The speed when the box arrived at the base is 3 m/s. a) what is the coefficient force between the box and the surface? b) how many work is done to move the box downward...

The work done by a conservative force on a closed curve is zero but why it isn't true for the non conservative force?

Homework Statement A 1.0 kg body is at rest on a friction-less horizontal air track when a constant horizontal force F acting in the positive direction of an x-axis along the track is applied to the body. A stroboscopic graph of the position of the body as it slides to the right is shown in...

1. The position x of a particle moving along x-axis at time t is given by the eqn, t=(√x)+2.,where x is in m and t is in s. Find the work done by force in first 4 sec2. W=F.s=mas I first found out x using the given eqn nd then went blank as there was no force or mass given. But the ans is 0

1. The Question Unable to find the work done by spring on the object sliding down the rod as shown below: Homework Equations Work Done by Spring Force : -1/2 * KΔx2 --(1) where k = Spring Constant Δx = Change in Spring Length[/B] 3. Where the problem occurred While seeing the solution...

1. A box of mass m = 59.0 kg (initially at rest) is pushed a distance d = 83.0 m across a rough warehouse floor by an applied force of FA = 204 N directed at an angle of 30.0° below the horizontal. The coefficient of kinetic friction between the floor and the box is 0.100. Determine the...

Homework Statement In the figure, a 700-kg crate is on a rough surface inclined at 30°. A constant external force P = 5600 N is applied horizontally to the crate. As the force pushes the crate a distance of 3.00 m up the incline, the speed changes from 1.40 m/s to 2.50 m/s. How much work does...

Homework Statement Two identical 0.50-kg carts, each 0.10 m long, are at rest on a low-friction track and are connected by a spring that is initially at its relaxed length of 0.50 m and is of negligible inertia. You give the cart on the left a push to the right (that is, toward the other cart)...

Homework Statement Homework Equations Conservation of Energy: ∑T1+∑U1-2=T∑2 The Attempt at a Solution ∫[/B](600+2s2)ds - 100*9.8*15 = (1/2)mv2. However, the term of work done by the force is less than the term of work done by gravity! The book has a solution, which is exactly this...

I know work done by conservative forces= - ##ΔU##=##ΔK.E## But I have a question.Does it mean work done by all the conservative forces present (in a particular physics problem)= - ##ΔU##=##ΔK.E## or just work done by a conservative force= - ##ΔU##=##ΔK.E## I mean let's say a problem in physics...

Homework Statement Kids are pulled 2km around a town in a wagon,The handle of the wagon is on an angle of 30 degrees from horizontal and requires 200N to maintain constant velocity. Determine the amount of work done against non‐conservative forces on this walk. Δx = 2km = 2000m angle θ = 30...

Hello all. I have a doubt about the work done by friction force on a wheels , in two diferent situations: a) In Morin's mechanics book, chapter 5 (page 146) he considers the situation in which a car is braking without skidding. He claims that the friction from the ground on the tires causes...

Homework Statement At a waterpark, sleds with riders are sent along a slippery, horizontal surface by the release of a large, compressed spring. The spring with a force constant k = 4300 N/m and negligible mass rests on the frictionless horizontal surface. One end is in contact with a...

Homework Statement Refer to plot attached. Homework Equations (a)Find the work done by a monatomic ideal gas as it expands from point A to point C along the path shown in the figure. (The horizontal axis is marked in increments of 25 m3.) (b) If the temperature of the gas is 215 K at point A...

Homework Statement In your design of an experimental spring powered model car, you note that the speed of the car (mass Mc) increases as the car travels further. The exact relationship is that v(x) = C|x|, where C is a constant and x is the position of the car with respect to the starting...

If I lift a ball of mass 5 kg from ground level to 1.5 meters above ground level and then throw it from this point up to a height of 10 meters, what is the work done by me on the ball? Is the following the correct way to solve this problem? Person only applies force to the ball for 1.5 meters...

can you help me check if these two statements are true? 1. work done by non-dissipative force is independent of the path that it takes ( ie: gravity) 2. work done by dissipative force is dependent of the path that it takes (ie: friction) Huge thanks!

Homework Statement I've encountered an answered problem in this book titled, "Physics for Scientists and Engineers with Modern Physics, 9th Ed" by Serway at page 187. So there is a spring which is hung vertically. 1. The first condition was the spring at an equilibrium state (ΔX=0) 2. The...

I know you guys all understand what work done is defined. I am wonder how work done is defined. Why does it define in this mathematical form? Also, how do we know 1 energy calculated by work formula = 1 energy of other form

Homework Statement Problem: A sample of dry air has an 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 perfromed by the sample under the...

Homework Statement Hi, I am stuck with the following question: The graph (attached) shows how the Moon's gravitational pull F on a lunar lander varies with the distance 'h' from the Moon's surface. Estimate the work done by the pull of the Moon on the lunar lander as it approaches the lunar...

Why work done by a force was taken as dot product between force applied and displacement caused?

Hi, I would like to evaluate the required work to create a 1 T field with a permanent magnet. I saw a few formulas on the internet, but I don't know how to use them correctly. The main one are B={{\mu }_{0}}\left( H+M \right) {{W}_{mag}}=\frac{{{B}^{2}}}{2{{\mu }_{0}}}Vol Let's say I know all...

Suppose we have an electron in a uniform electric field by two parallel plates A and B. (Plate A is higher in potential than B), and we have an electron on plate B moving to A, am I right to say that the electron is losing its own EPE to convert it to KE and there is no work done by electric...

Homework Statement There is a uniform electric field, E = 270 N/C, parallel to the xz plane, making an angle of 32o with the positive z axis and an angle of 58o with the positive x axis. A particle with charge q= 0.475 C is moved from the point (xi = 2.0 cm, yi = 0, zi = 0) to the point (xf =...

Homework Statement Consider a point charge Q placed at point O.Consider any point p in the field of the Q.Charge q is placed at point p.Charge q is then moved from point p to s the distance i=between p and s is dr.Calculate work done. y Homework Equations ##dW=##-##F^→.dr^→## The Attempt at a...

Homework Statement Homework Equations ∫F⋅dr=W The Attempt at a Solution

Homework Statement A block of mass m is released from rest on a smooth inclined plane (wedge). The wedge itself is resting on a smooth horizontal surface. The block undergoes a vertical displacement of h. Assume that the height of the incline is h and the length of the incline is h cosec θ...

1. Find the work done by a gas if both pressure and volume increase at the same time, where the pressure rises as the square root of specific volume rises. I know that work done is the integral of pdV, but I'm not sure how to set up this same integral when there is a specific relationship where...

Homework Statement Homework Equations W=-ΔU for conservative force. The Attempt at a Solution Let all three forces be conservative. Since particle comes back to where it was, ΔU=0. Hence ΔUAB+ΔUBC+ΔUCA=0 Hence WCA=-WAB-WBC For case A, if both WAB, WBC>0, then WCA<0. Else its greater than...

Homework Statement a metal rod of length "L",cross sectional area "A",young modulus "Y" and coefficient of linear expansion "α " is heated to "t" degree celsius .The work that can be performed by the rod when heated is Homework Equations work done by rod when heated=1/2 force exerted by...

When a particle is attached to a rope and rotated, then tension acts perpendicular to displacement and work done is zero. But I am thinking about this case (top view): Here, the rope is attached to a vertical cylinder and the particle is given a velocity perpendicular to the rope. The length...

Homework Statement The potential energy ##U## of a particle of mass 1kg moving in x-y plane obeys the law ##U=3x+4y##. x and y are in meters. If the particle is at rest at (6,8) at time t=0, then find the work done by conservative force on the particle from initial position to the instant when...

If we apply force on a small mass in open space, then it will cover infinite displacement. Then would the mass have infinite work done?

I am a little confused about the work do the to lift an object. I know that in lifting an object a net force must be applied in order to increase its velocity, but when the object stops, gravity applies an equal but opposite force, which means that in lifting an object no net work on the object...