# Work constant velocity

You are pushing a refrigerator across the floor of your kitchen. You exert a horizontal force of
291N for 7.5s, during which time the refrigerator moves a distance of 2.7m at constant velocity.

(a) What is the total work (by all forces) done on the refrigerator?

(b) What is the work done by friction?

How can I calculate the work done by friction if a mass isn't provided and there is no acceleration obviously since there is a constant velocity?

tiny-tim
Homework Helper
welcome to pf!

hi nbroyle1! welcome to pf! How can I calculate the work done by friction if a mass isn't provided and there is no acceleration obviously since there is a constant velocity?

that's right, the acceleration is zero and the velocity is constant …

so use the work energy theorem Thanks, but don't I need the mass for the work energy theorem also?

Net work=1/2mv(final)^2-1/2mv(initial)^2

Is the friction force equal to the force applied since it is a constant velocity? or would that just meant that the object isn't moving at all?

tiny-tim
Homework Helper
(try using the X2 button just above the Reply box )

in this case, 1/2mv(final)2-1/2mv(initial)2 = … ? doesnt it just equal zero since the velocity is the same?

tiny-tim
yes 