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When do you use W=Fd vs. W=Fdcos(theta)?
Hope you guys understand my question.
Hope you guys understand my question.
Fd vs, Fdcos0
- Thread starter DieselD
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Fdcos is used when the force being applied isn't in the same direction as the direction the work is being done in.
Remember: cos of 0 is 1. so when the force is being applied fully in the same direction as the work is being done, then it reduces to W = Fd.
Remember: cos of 0 is 1. so when the force is being applied fully in the same direction as the work is being done, then it reduces to W = Fd.
The theta is there because the only part of the force that matters is the component that is helping you go in the direction that you are going in.
A good (but tricky) example of this is work done by a magnetic field. Force of a magnetic field is: F (vector) = q<v x B>.
Cross product only involves the perpendicular components. This means that the force from a magnetic field on a charged particle will always be perpendicular. Since the force is perpendicular to the direction its going, theres no work, theta = 90.
A good (but tricky) example of this is work done by a magnetic field. Force of a magnetic field is: F (vector) = q<v x B>.
Cross product only involves the perpendicular components. This means that the force from a magnetic field on a charged particle will always be perpendicular. Since the force is perpendicular to the direction its going, theres no work, theta = 90.
