Learn more physics!
Q:
Hello,
power=Fv where F is force and v is velocity. what if the object accelerates and there is a range of velocities...which v do we take? or do we take the average velocity (u+v)/2 so that power=F(u+v)/2 ??
- Anonymous (age 15)
A:
Power mean the rate at which work is being done at some particular time. So the power at that time depends only on
F and
v at that time.
Now if you want the average power over some period, it depends on what's changing. If
F is fixed, then of course
v changes. But for fixed
F the average
F•v is just
F•vave, as you suggested. If both
F and
v are changing, there's generally no shortcut to avoid actually averaging
F•v.
Mike W.
(published on 01/07/2011)
Follow-up on this answer.
