Rotation and power problem, help

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The discussion revolves around calculating the power needed to lift a 15 kg bucket at a constant speed of 0.2 m/s using a winch with a radius of 0.03 m and a handle length of 0.4 m. The correct power required is identified as 29.4 W, while the user initially calculated 11.26 W. To find the necessary force, the user is advised to use the torque formula, which relates radius, force, and torque. Clarification is provided that "module" refers to the magnitude of the force. The conversation emphasizes the importance of sharing calculations for troubleshooting errors.
Cyannaca
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Hello, I would like it if anyone could help me with this problem

A bucket of 15 kg is lifted up from a well at a constant speed of 0,2 m/s. The cord rolls up around a winch (radius 0,03m). The winch is turned with a handle 0,4m of length
a) What power is necessary bring the bucket up?
b) If the force applied is always perpendicular to the handle, what is the module of the necessary force?

The answers are 29,4 W and 11 N and I don't know what is wrong but I always get 11,26 W :mad:
 
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What are your calculations?
 
I finally solved a (afer half an hour!) but now I really don't know how to do b
 
"module" means the same as "magnitude".
Does that help?
 
Welcome to the forums, Cyannaca!

Can you please post your calculations, so we can help find your error? Forum rules, plus it makes it much easier for everyone.
 
Ok, so I need to use Torque= radius*F* Thank you!
 

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