The gravitational potential energy is given by the formula,

PE_{g\ }=\ mgh , where m is the mass of the object , g is the acceleration due to gravity, and h is the height of the object.

PE_g\ =\ 0.5\ kg\ \times9.8\ \frac{m}{s^2}\ \times3\ m\ =\ 14.7\ kg\ \frac{m^2}{s^2}\ =\ 14.7\ J

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What is the potential energy of a 2- kg book sitting on a shelf 2 ...

Mar 28, 2011 ... Use the formula for gravitational potential energy: PE = mgh (mass x gravity x height). Since you are using SI units, gravity is 9.8 ...

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