Finding units for power via Dimensional Analysis? Makes no sense

AI Thread Summary
Power is defined as the rate at which work is performed, measured in watts (W), which equates to joules per second (J/s). Joules, the unit of energy, can be expressed as Newtons multiplied by meters (Nm). A Newton is the force needed to accelerate a one-kilogram mass by one meter per second squared. To derive the units for power through dimensional analysis, one can start with the relationship of work as force times distance and then express it in terms of kilograms, meters, and seconds. The discussion emphasizes the importance of understanding these relationships to clarify the units of power.
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Homework Statement



"Power is the rate at which work is performed.

Power is signified by W for watts.

Power is also the amount of energy transmitted in a unit of time (s).

Energy is measured in joules. Joules have the units of Newton∙meters.

A Newton is a unit of force. It is equal to the amount of force required to give a 1 kilogram mass and acceleration of one meter per second squared."

Using the aforementioned information, determine the units for power by completing a dimensional analysis.


Homework Equations


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The Attempt at a Solution



Ok so I know that the units for power are Joules/seconds.. How would you go about getting this by dimensional analysis at all?

So I've done

P = J/s

Power (P) = Work (W)/time (t)
P is in Watts (W)
Watts is J/s

Not sure at all what to do, this is worded so weirdly.. If anyone could help me see what exactly to do, that'd be appreciated.
 
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Currently, you have done this question by working backwards. You were pretty much there.

The unit for Force is Newtons

Work = force * distance. Hence, the units for work is Newtons * distance (Nm) which is equivalent to Joules.

Now, reapply this to what you've already done and you're pretty much there.
 
It might be asking you to get strictly down to units of kg, m, and s.
 
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