Total force resisting the forward motion of a boat at a speed

AI Thread Summary
To determine the total force resisting the forward motion of a boat at its top speed, the engine's power output must equal the resisting power of the water. Given that the engine is rated at 100 kW and the boat reaches a speed of 70.0 km/h, the power can be expressed as the product of force and velocity. The relationship can be formulated as Power = Force x Velocity. By rearranging this equation, the total force resisting the boat's motion can be calculated. This analysis confirms that at maximum velocity, the engine's power is fully utilized to counteract the resistance from the water.
sparkle123
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Problem:
A boat powered by an engine rated at 100 kW can reach a top speed of 70.0 km/h. What is the total force resisting the forward motion of the boat at this speed?

I don't know which equations to use :(
 
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Well if I am correct, then at that max velocity the engine is using all of its 100kW of power to maintain that speed. So you know that to maintain constant velocity the power output of the engine must be equal to the resisting power of the water.

Now if the work done over any distance 'x' by the water is F*x, then what is the power?
 
Got it! Thanks for your help!
 

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