What is Work done: Definition and 1000 Discussions

In physics, work is the energy transferred to or from an object via the application of force along a displacement. In its simplest form, it is often represented as the product of force and displacement. A force is said to do positive work if (when applied) it has a component in the direction of the displacement of the point of application. A force does negative work if it has a component opposite to the direction of the displacement at the point of application of the force.
For example, when a ball is held above the ground and then dropped, the work done by the gravitational force on the ball as it falls is equal to the weight of the ball (a force) multiplied by the distance to the ground (a displacement). When the force F is constant and the angle between the force and the displacement s is θ, then the work done is given by:




W
=
F
s
cos
⁡

θ



{\displaystyle W=Fs\cos {\theta }}
Work is a scalar quantity, so it has only magnitude and no direction. Work transfers energy from one place to another, or one form to another. The SI unit of work is the joule (J), the same unit as for energy.

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  1. F

    Solving Work Done by Pushing a Lawnmower

    Homework Statement A man pushes a lawnmower with a force of 200N. If the vertical component of this force is 80N how much work is done in pushing the lawnmower 6.0m horizontally? Homework Equations Work=force x distance The Attempt at a Solution Firstly I have to find the angle to the ground...
  2. beamie564

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  3. Monsterboy

    Work done by compressed air on the piston

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  4. James Ray

    Work done on ideal monatomic gas in adiabatic process

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  5. S

    Why work done on a system causes heat to flow out of it?

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  6. R

    How to calculate impulse required to move an object vertical

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  7. K

    Work done by a 20% efficient heat engine

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  8. N

    Finding work done using definite integrals

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  9. N

    Electrostatic potential a a point, the pluses and minuses

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  10. Biker

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    Homework Statement It is not an actual questions, Just misconceptions For example, Lets find the work done over a distance in an electric field Homework Equations v = PE/q E = F/q F = k q1 q2 /r^2 W = fd The Attempt at a Solution I didn't study calculus yet but I am going to because I need to...
  11. D

    Calculating Work on a Charged Particle in an Electric Field

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  12. I

    Potential Difference Across Capacitor Regions and Work Done

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  13. B

    Work Done by Theme Park Machine on Rider

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  14. Destroxia

    Work done by Three Dimensional Inverse Square Field

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  15. Le_Anthony

    Work Done by Crane: Calculating Force & Acceleration

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  16. Le_Anthony

    Calculating Work Done by a Spring

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  17. S

    Rotational work done by static friction?

    Homework Statement A disk roll without slipping down a incline plane. Identify the forces acting on the disk, explain qualitatively which of these forces do work. Homework Equations The rotational work is given by W=\int \tau_z d\theta (1) , where \tau_z is the component of the torque...
  18. Blockade

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    I need to find the work done with springs but I don't understand this equation too well, can someone help me know what are each variable and how to find each of them? WH - fF*d = ΔK + ΔUs + ΔUg? I know that "WH" is the work done by the hand and that "fF*d" is force of friction * displacement...
  19. T

    Work done using time, velocity and mass?

    Homework Statement The law of conservation of energy applies to the motion of vehicles. Find the work done on a 1200kg vehicle when it slows from 90kmh-1 to 50kmh-1 in 8.0 seconds. Homework Equations W=1/2mv^2 - 1/2mu^2 The Attempt at a Solution [/B] W=0.5*1200*50^2 - 0.5*1200*50^2
  20. toforfiltum

    Why is there no work done on gas from Q to R?

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  21. V

    Finding the WORK done by a crane in lifting a load

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  22. enh89

    Physics problem involving work on pump

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  23. Teameister

    Work done moving charge near a line of charge

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  24. B

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  25. Stella.Physics

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  26. ecoo

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  27. Brandon 456

    What is the Work Done on the Person+Sled System in an Amusement Park Ride?

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  28. ccarit3007

    What is the work done on a comet orbiting a star?

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  29. H

    Why is there no virtual work done by a rolling friction?

    Why is there no virtual work done by a rolling friction? In pure rolling, is the virtual displacement parallel or perpendicular to the surface? I believe it can't be perpendicular because the object is not allowed to lose contact with the surface. But if it's parallel, then there must be a...
  30. DevonZA

    Calculate the work done when a conductor moves through a mag

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  31. R

    What are some approaches for estimating the work done up to fracture?

    Good day everyone! i have a problem dealing with the fracture analysis. We all know that the work done per unit volume is equal to the area under the curve of stress-strain curve or we can express it in terms of integral form, and if we're looking at necking point stress can be express in this...
  32. x2017

    How Much Work Does the Landing Mat Perform on Yelena Isinbayeva?

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  33. x2017

    Work Done on 100 kg Block by 100 N Force in 4s

    Homework Statement A 100 N net force acts on a 100 kg block (initially at rest) for 4s a. How much work was done on the block? (1) b. What is the block’s velocity after the 4 s? (1) c. How much energy does the block have after this time?(1) d. The 100 N net force is no longer acting on the...
  34. E

    Calculating Work Done in Inflating a Square Balloon

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  35. G

    Work done by a gas in a piston

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  36. J

    Velocity of a point charge from work done

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  37. J

    Work done by moving a point charge

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  38. M

    Work done by a uniform Ring of Charge (due tomorrow

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  39. V

    Work done on a stationary bicycle?

    So when someone is simply cycling on a stationary bike, is that person doing any work? Because work is Force * distance. But there's no distance here, right? Is work simply the energy then?
  40. xareu

    Work done by permanent magnets

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  41. ElPimiento

    Work that must be done to charge a spherical shell

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  42. henrco

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  43. M

    Total Work done on a Capacitor

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  44. N

    How to evaluate the work done by spring without applying calculus

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  45. Rumplestiltskin

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  46. N

    Calculating Work Done by Car Engine

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  47. Rumplestiltskin

    Finding Work and Force in a Thrown Ball Problem

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  48. A

    Does a magnetic field always do work?

    Magnetic field do no work. Is this always true? If so then what is the explanation of that crane thing?
  49. K

    How Is Work Calculated in Thermodynamic Processes?

    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...
  50. Y

    What Is the Potential at the Center of Concentric Metallic Spheres?

    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...
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