Work Definition and 999 Threads

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. gibberingmouther

    Work to stretch a spring question (nvm, figured it out)

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  2. isukatphysics69

    Find the work done by the spring force on a box

    Homework Statement Homework EquationsThe Attempt at a Solution Wspring = ∫-k*xdx limits of integration are 12 and 0 So [0 - .12^2/2]*172 = -1.24J of force Getting 1.8/2 points for this anser
  3. B

    Thermodynamics Compressor Work (1st law question)

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  4. Clara Chung

    Question about work energy theorem

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  5. S

    Why is W Tot not equal to W Glider on Spring in Newton's Third Law?

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  6. P

    How does this spectroscope work?

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  7. Cheesycheese213

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  8. P

    Determine the work done by the force due to gravity

    Homework Statement If the height of a frictionless incline is h. Determine the work done by the force due to gravity F as the crate of the mass m slides down the incline Homework Equations W=Fd cos (theta ) Force due to gravity perpendicular to incline= mg cos(theta) The Attempt at a...
  9. E

    Finding the electric field at point - Can someone check my work?

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  10. T

    Would this work? (air filled tube inside a water filled container)

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  11. M

    B G11 Metric Tensor: What is it & How Does it Work?

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  12. kyphysics

    Is Dec. '17 work paid Jan. '18 taxable for 2017?

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  13. pokemon123

    Understanding Work with Conservative Forces | Physics

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  14. MathematicalPhysicist

    A Why Do Feynman Rules Successfully Model Particle Interactions?

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  15. H

    Heat and work when temperature increases by 1 degree

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  16. F

    The work done by the electric field between two plates

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  17. H

    Work done for isothermal process in terms of Helmholtz func

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  18. C

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  19. harambe

    B Constant Force: Energy Conservation & Path Independence

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  20. L

    About the total work done loading and unloading (setting down) an object

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  21. C

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  22. Hydrous Caperilla

    Thermodynamic Work: Non-Conducting Piston & Cylinder

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  23. Fig Neutron

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  24. doglover9754

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  25. BlackJ

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  26. A

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  27. K

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  28. Pushoam

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  29. A

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  30. A

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  31. D

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  32. The Bill

    How do the nozzles on spray bottles work when misting?

    I looked up misting nozzle design, but the results I found referred to two types of industrial misting nozzles which don't match up to what a spray bottle looks like at all. I tried looking up design elements of spray bottle nozzles specifically, but all I found were details on how the pump...
  33. J

    How does does a DC generator work?

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  34. ZiHao

    How and Why Peltier Tiles work?

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  35. J

    Work done by friction on smaller block

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  36. binbagsss

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  37. J

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  38. K

    MHB Multivariable calculus line integral work

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  39. grandpa2390

    Why Won't My Matlab Code Work?

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  40. F

    Pumping Water -- Please check my pump system design work

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  41. B

    Change of Temperature from Work in Hydrostatic System

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  42. almosthavoc

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  43. E

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  44. M

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  45. grandpa2390

    Is Work Being Done When a Car Travels at Constant Velocity Against Friction?

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  46. FlimFlam

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  47. P

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  48. karush

    MHB 17.7.07 other orders usually work well and are occasionally easier to evaluate

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  49. Grands

    How important is the work done by people who work in finance?

    Hi guys. Due to the reason that I do not have a great knowledge related to finance, I wanted to ask if someone can simply explain me how important is for the society, the work of the people that work in the finance. How their job is useful for the people? Thanks Grands.
  50. JustAStudent

    Work to move electron/proton between the plates of a charged capacitor?

    Homework Statement A charged capacitor consists of two large flat plates, one with positive charge +Q and the other negative charge -Q. An external agent trans an electron from the positive plate to the negative and also transfers a proton from the negative plate to the positive plate. There is...
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