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What is the potential energy of a 3.00 kg object at the bottom of a well 10.0 m deep as measured from ground level ? Explain the sign of the answer. (b) How much qirk is required to lift a 3.00 kg object from the bottom of the well 10.0 m deep

User Chriopp
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The potencial energy is given by the following formula:


E_P=\text{mgh}

Where "m" is the mass, "g" is the acceleration of gravity, and "h" is the height. Since the height is below the reference point it has a negative sign. Replacing we get:


E_P=(3kg)(9.8(m)/(s^2))(-10m)

Solving the operation:


E_P=-294J

The negative sign indicates that the object is below the zero point.

b. Since the work is equivalent to:


W=Fd

The force that acts on the object is equivalent to its weight and the distance the height, therefore:


W=\text{mgh}

Replacing:


\begin{gathered} W=(3\operatorname{kg})(9.8(m)/(s^2))(10m) \\ W=294J \end{gathered}

User Ndberg
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