Lifting a canister with a pulley

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To lift a canister with a mass of 25 kg at a constant speed using a pulley system, the force exerted must equal the weight of the canister, which is calculated as mg, where g is the acceleration due to gravity (approximately 9.81 m/s²). The discussion indicates a misunderstanding regarding the pulley system's mechanical advantage, which is 2:1, meaning the force required is halved. The user initially calculated the force needed without considering this advantage, leading to confusion about the results. The correct approach involves adjusting the force calculation based on the pulley configuration. Understanding the mechanics of the pulley system is crucial for accurate force determination.
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In the figure, a cord runs around two massless, frictionless pulleys; a canister with mass m = 25 kg hangs from one pulley; and you exert a force F on the free end of the cord. What must be the magnitude of F if you are to lift the canister at a constant speed?

Here i know that the answer is mg*d. So 25*9.81*0.066m but i am not getting the answer. as i have in the book. in the previous question was To lift the canister by 3.3 cm i had to lift it by 6.6 cm so i don't what i am doing that i s wrong. Thanks for the help
 
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There is no figure associated with your post, but from the last thing you said, it sounds like the pulley arrangement gives you a 2:1 force advantage. Did you take that into account in your calculation for the first question?
 
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