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. PhizKid

    Work done by a gas with only pressure and volume

    Homework Statement An ideal diatomic gas undergoes an adiabatic compression. Its initial pressure and volume are 1.20 atm and 0.200 m^3 and its final pressure is 2.40 atm. How much work is done by the gas?Homework Equations W = -\int p \cdot dVThe Attempt at a Solution So after integrating I...
  2. Y

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  3. A

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  4. N

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  5. G

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  6. L

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  7. L

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  8. M

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  9. C

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  10. P

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  11. E

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  12. I

    Work done by friction on an incline plane

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  13. D

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  14. C

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  15. Sneakatone

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  16. K

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  17. Z

    Work done on an incline plane with friction

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  18. deep838

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  19. R

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  20. T

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  21. S

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  22. T

    Why Does the Textbook Solution Use Average Pressure for Piston Work Calculation?

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  23. R

    Calculating work done by helicopter/gravity, kinetic energy and speed?

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  24. A

    Is the Force-Displacement Relationship Conserved in Energy Conservation?

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  25. Avi Nandi

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  26. P

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  27. R

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  28. W

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  29. Q

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  30. N

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  31. C

    Work done by gas expansion on piston

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  32. Saxby

    Isothermal exapansion, work done

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  33. D

    Calculating work done in draining water

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  34. R

    Finding r using point charges and work done by an electric force

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  35. D

    Work done to move a point charge

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  36. D

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    I want to show that the work done by compressing a container of gas with uniform pressure is -\int_{V_i}^{V_F} p(V)dV, where p(V) is the pressure of the gas as a function of volume. This equation was derived in my text for the special case of a piston, but I wanted a more general derivation...
  37. D

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  38. B

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  39. N

    Understanding Work Done and the Role of Force in Solving Problems | 360J Example

    I have always managed to solve problem asking how much work is being done but then once I start to think about the work being done I get confused. E.g A barrel of weight 200N is raised by a vertical distance of 1.8m by being moved along a ramp. The work done here would be 200 x 1.8 =360J . I do...
  40. T

    Work done by a force with a given equation

    Homework Statement A force acts on a particle and is given by the following expression: F(x,y)=2x^3 y^2 i+3xy^3 j What is the work done by this force in moving the particle from a position (x,y) = (0,0) to (4,2) along the path given by the curve y=√x ? Homework Equations I know...
  41. D

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  42. D

    The work done by an electric field in accelerating a charged particle?

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  43. R

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  44. P

    Which Statement is Correct: Ram & Shyam Work & Power

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  45. S

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  46. M

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    Hello 1- work done to push body forward is greater than to pull body backward what is the explanation for this?can you draw the two FBD in both cases ? 2- why is nail driven in wooden wall but not in the concrete wall ؟ I guess this is somehow related to Newton's third law Thanks
  47. B

    Why Is Work Done by Gravity Zero for a Satellite in Orbit?

    Okay, the problem is: A 1200~kg satellite is in a circular orbit around the Earth at a radius of 8.77\cdot 10^6~m. What is the work done by gravity when the satellite has gone a quarter of the war around its orbit? The acceleration due to gravity at the height of the satellite is 5.19\cdot...
  48. B

    Compute the work done by the force field.

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  49. L

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  50. O

    Find the work done by the force field F on particle moving along path

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