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    Crate being pushed varying force

    it all makes sense now. thanks for the help.
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    Crate being pushed varying force

    ok so we have the change in potentila enrgy = Wg but what are the calculations or formula for calculating Wa. that is what i need to understand. thnks
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    Crate being pushed varying force

    since it gets pushed sideways, the height changes vertically but the length of the rope remains the same. sqrt(15^2-5^2)=14.14
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    Crate being pushed varying force

    mg(df-di)=(9.8)(170)(14.14-15)=-1432.76J ? same as above i already calculated it?
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    Crate being pushed varying force

    but since it is a varying force, how would i use the scalar product, it isnt a constant force. should i only apply it to the final position where. what is the formula for Wa? since its the negative of Wg= mghcos180=-(9.8)(170)(0.86)=-1429 J. Wa should be +1429J but how can i calculate it...
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    Crate being pushed varying force

    Wa is the work done by the applied force. since at any point on the rope it is right angles to displacement cos90=0 so then tcos90=0. the answer in the book is 0 too. thats what i think.
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    Crate being pushed varying force

    so for a, are the calculations correct? tension will have its corresponding components, yes. and for c work due to tension is always 0 then (cos90) "why isn't the component of Force along x = M*g*Sinθ" how did you come to that conclusion??? EDIT: how would one calculate the Wa without setting...
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    Crate being pushed varying force

    for (a) gravity does not have any components. i think you misread the question. ive attached a diagram. for (b) since the change in kinetic energy is zero, mgh is equal to the negative of work for (c) i dont quite understand
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    Crate being pushed varying force

    given/known data A 170 kg crate hangs from end of rope length L = 15 m. You push horizontally on crate with varying force F to move distance d = 5 m sideways. (a) What magnitude be of F when crate is in final position? During crate's displacement, what are (b) the total work done on it, and (c)...
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    Speedboat Pulling Skiers

    Homework Statement 300 kg speedboat is pulling two 25 kg skiers using ropes. Each rope makes an angle of 30 with the boat axis. Each rope exerts 500N force and acc. is 2m/s^2. What force must the boat exert on water to keep skiers moving? Homework Equations a=Fnet/m The Attempt at a...
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    Newtons Second Law

    [SOLVED] Newtons Second Law Homework Statement On a force/mass vs acceleration graph where force/mass is horizontal, what does the slope represent? Homework Equations The Attempt at a Solution My calclations: ex. (2m/s^2 - 1m/s^2)/(3 N/kg - 1N/kg) =.5 (m/s^2)/(N/kg)...
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    The Flea

    thanks i get it now
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    The Flea

    [SOLVED] The Flea Homework Statement A flea, jumping with its highest possible initial speed, can jump to a maximum vertical height of 1 cm. What is the time spent in the air by the flea during the vertical jump? What would be the time spent in the air if the flea were instead to leave the...
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