Work in the vertical direction

[Meredith92]

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If the displacement of an object is in the y direction, then wouldn't work be done vertically? For example, if someone lifts a block straight up from the ground would they be doing work? Reading through tbr makes it seem like work can only be done in the delta x direction but
I'm getting myself confused.

 

[Meredith92]

Oh I think i understand now.. You can apply delta y Fsin(theta)=W which equals mgh.

 

[theCLE]

The thing to keep in mind it that if the force is perpendicular to the distance, then there is no work done. So a guy carrying his briefcase is moving in the X direction, but the force in his shoulders is totally in the Y direction = No work done. However, if the guy picks up his briefcase so it doesn't get chewed by the dog, then the force is in Y dir, and the distance the briefcase was moved is in the Y dir...THUS...work is done!