# Working with power, force and efficiency in a speed problem

A 7.5 x 10^4 W motor that is 75% efficient exerts an average force of 3.5 x 10^3 N to move a boat at a constant speed. How fast is the boat moving?

NOTE: efficiency = output/input.

Motors are rated as to their input. 7.5 x 10^4 is the power input.

https://brainmass.com/physics/power/working-power-force-efficiency-speed-problem-6335

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The output power of a motor has the relation with the force it ...

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