Respuesta :

Given,

Mass, m = 50 kg

Potential energy, PE = 4,120.7 J

The potential energy of the object is calculated by the formula,

[tex]PE=mgh[/tex]

Here, g is the acceleration due to gravity calculated as

[tex]g=9.81m/s^2[/tex]

Calculate the height of the object.

[tex]\begin{gathered} 4,120.7\text{ J = 50 }kg\times9.81m/s^2\times h \\ h=\frac{4,120.7}{50\times9.81} \\ h=8.40\text{ m} \end{gathered}[/tex]

Thus, the height at which a 50 kg object must be lifted is 8.40 m.