i need major help with a physics problem!! "power output?" please help i have a...

[cocomademoiselle]

...test tomorrow ? im a bit confused here... is poweroutput the same as power?

suppose you are moving a 300 N box of books. you exert a force of 60.0 N to push the box across the floor 12.0 m in 20.0s. what is your power output?


how do i solve that? >____<

oh and does anyone know the equations for mechanical advantage, mass, gravitational potential energy, kinetic energy, efficiency?

[Ernst S]

Power is energy per time. Power output is the power that is measurable at the output interface of a system, machine, or human.
In this case of the question a human is doing work. All the power in his body while doing the required work is more than the mechanical output power. (Heat power, internal power losses, internal power requirements for digestive system, heart, respiration etc)

Mechanical power is: Force times distance divided by time

60N * 12m / 20s = 36Nm/s = 36J/s = 36W

For your last question: Buy a good book on classical physics,
read it and learn. Also get acquainted with dimensions and their SI units.

[KJH,SQ`d]

Mechanical advantage is simple..... weight times arm equals force.....example,, if You exert 10 lbs on a 10 to 1 arm, You achieve 100 lbs of force ( but You will exert 10 in of movement, in order to move the work 1 in)....perhaps You could just throw the problems over here, and I'll solve for them and try to teach You as We go.......ther are so many ways to solve for Mech advantage that it could take days, if not weeks or years to learn them all, capiche? KJH

[KJH,SQ`d]

Mechanical advantage is simple..... weight times arm equals force.....example,, if You exert 10 lbs on a 10 to 1 arm, You achieve 100 lbs of force ( but You will exert 10 in of movement, in order to move the work 1 in)....perhaps You could just throw the problems over here, and I'll solve for them and try to teach You as We go.......ther are so many ways to solve for Mech advantage that it could take days, if not weeks or years to learn them all, capiche? KJH