Is there such formula? There probably is of course, but i would like a very concise description of how to derive it, in order to better understand myself. Thank you in advance.
-
1$\begingroup$ Here is a link to a website that includes much explanation: physicsclassroom.com/calcpad/energy. Notice that the original equation for work is a trigonometric function, because you must take into consideration the angle between the force vector and the displacement vector. $\endgroup$– ErnieAug 29, 2015 at 13:04
1 Answer
Yes there is, first consider the original power formula
$P = w/t$
Now we know that work is equal to force.displacement (both vectors)
$P = (F.D)/t$
$P = F.(D/t)$
Displacement over time is velocity, so
$P = F.V$
Hence power can be stated as a dot product of the vectors force and velocity
Expanding the dot product
$P = FV\cos\theta$
Where $\theta$ is the angle between force and velocity, $F$ is magnitude of force, $V$ is magnitude of velocity.